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publisherblogs · 4 years

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chemistry blog

1. Introduction

Today, over 90% of the world‘s organic chemicals are produced from petroleum, and 85% of crude oil is used for the production of transportation fuel. Due to the depletion of fossil resources and global warming concern, considerable attention was focused on the conversion of renewable biomass to chemicals and fuels. Among these chemicals, 2,5- furandicarboxylic acid (FDCA) has received significant attention as potential replacement for terephthalic acid for the production of poly (ethylene terephthalate) (PET). A FDCA-based polymer poly(ethylene-2,5-furandicarboxylate) (PEF) has been prepared and investigated, which showed comparable properties to PET. FDCA was also listed as one of the 12 key value-added chemicals from biomass by the US Department of Energy.

Currently, there is a growing attention on the production of fuels and commodity chemicals from the renewable resources. Biomass is one of the most abundant renewable resources in the earth. Through bio refinery, both liquid fuels and organic chemicals can be generated from biomass.

5-Hydroxymethylfurfural (HMF), one of the 12 top value added chemicals, has received great attention for the past decades. HMF owns one hydroxyl group, one aldehyde group and furan ring, and thus it can be served as versatile precursor for the synthesis of a variety of chemicals and value added fuels. For example, the catalytic hydrogenation of HMF can generate 2,5-dimethylfuran, which has a high energy density. Through the catalytic oxidation reactions, several kinds of furanic compounds with very important application in many fields can be produced, including 2,5-diformylfuran (DFF), 5-hydroxymethyl-2-furancarboxylic acid (HMFCA), 5-formyl-2-furancarboxylic acid (FFCA).

HMF can be obtained from the dehydration product of C6 based carbohydrates, such as fructose, glucose, cellulose even lignocelluloses. The dehydration of carbohydrates (mainly fructose) has been early performed by the use of mineral acids as the catalysts. However, the use of mineral acids exhibited many drawbacks such as their corrosive and non-recyclable nature, and its wastes to environment, which is unsuitable in the chemical industry. Catalytic conversion of carbohydrates into HMF over heterogeneous catalysts can overcome the drawbacks caused by the use of homogeneous catalysts. Besides to the catalyst, the dehydration of HMF is also reported to be affected by the reaction solvent. Water is a green solvent for chemical reaction, but it is not suitable for the dehydration of carbohydrates to HMF, as the water can accelerate many side products such as levulinic acid (LA), formic acid (FA) and humins. In contrast to water, ionic liquids with unique physicochemical properties are proved to be good reaction medium for the conversion of carbohydrates into HMF. However, the large-scale synthesis of HMF is limited by the high cost of ionic liquids. Encouragingly, dimethylsulfoxide (DMSO) shows high ability to dissolve carbohydrates, stabilize HMF and reduce side-reactions. Thus, good results of the dehydration of carbohydrates can also be attained in DMSO.

The production of HMF has been extensively reviewed by many researchers, including some analyses of the catalytic systems used and the underlying mechanisms. The availability of the functional groups, C=O, C-O and furan ring, allows HMF some flexibility in its conversions by multifunctional catalysts and in the future production of many value-added chemicals.

Hydrogenolysis of the C=O and C-O groups of the side chains can lead to 2,5-dimethylfuran (DMF), a promising fuel candidate with similar properties to commercial gasoline.Hydrogenation of the C=O bonds and the furan ring offers access to useful monomers for bio-based polyesters, including 2,5-dihydromethylfuran (DHMF) and 2,5- dihydromethyltetrahydrofuran (DHMTHF). Etherification of HMF can afford 5-ethoxymethylfurfural (EMF), which was an excellent additive for diesel. Opening of the furan ring and subsequent hydrogenation can produce 1,6-hexanediol, an important diol for the synthesis of caprolactone and caprolactam. Long-chain alkanes with targeted molecular weight can be obtained by aldolization/crotonization of the side-chain C=O group followed by complete hydrogenation. 3-(Hydroxymethyl)cyclopentanone (HCPN), a raw material for producing fragrances, drugs and solvents, can be produced by hydrogenation and ring rearrangement reactions. A DielsAlder reaction of DMF can yield p-xylene (PX). Finally, oxidation of the C-O/C=O bonds gives 2,5-diformylfuran (DFF) and 2,5-furandicarboxylic acid (FDCA), which serve as building blocks for polymers.

FDCA can be prepared by oxidation of HMF, while HMF is prepared by acid-catalyzed dehydration of sugars or cellulose. HMF could be oxidized to FDCA with stoichiometric oxidants, metal catalysts, or enzyme. Among these, the catalytic conversion of HMF with oxygen is more attractive. The most studied catalysts are Au, and Pt usually with base additive and at elevated temperature. High or even quantitative yield of FDCA can be obtained. However, the product obtained from these catalytic systems under basic condition is the salt form of FDCA which cannot be directly used in polymer industry. The separation of FDCA from aqueous system usually requires the addition of strong mineral acids such as HCl and H2SO4 pH =1, where FDCA will then be precipitated from the solution as white precipitate. In contrast, the conversion of HMF to FDCA under base-free conditions would eliminate the need to convert FDCA salt to FDCA, making the system greener with less waste generated.

In fact, our study for the conversion of HMF to FDCA with Ru/C catalyst started with the addition of equivalent amount of base. It was found that stronger base led to lower FDCA yield. For example, when NaOH was used as base, it gave only 69% FDCA yield. The color of the reaction mixture turned brownish due to the degradation of HMF at higher pH. To minimize this side effect, weak bases were tested in the reaction system. It is clear that the weaker the base used, the higher the FDCA yield was obtained.

On the other hand, with limited fossil resources, the search for chemicals and fuels from renewable sources has recently attracted considerable interest. Biomass is the only carbon containing renewable resource. 5-Hydroxymethylfurfural (HMF) is regarded as a value-added platform chemical. Several important furan chemicals can be obtained by the oxidation of HMF including 5-hydroxymethyl2-furancarboxylic acid (HMFCA), 2,5-diformylfuran (DFF), and FDCA. In contrast to HMFCA and DFF, FDCA has received a great deal of attention as an excellent candidate as a monomer for the synthesis of polymers. FDCA has the ability to replace terephthalic acid in the synthesis of polyamides, polyesters, and polyurethanes. There are many reports on the oxidation of HMF into FDCA. In one such report, homogeneous metal acetate catalysts including Co(OAc)2, Mn(OAc)2, and HBr were applied for the synthesis of FDCA from HMF at 70 bar air pressure in acetic acid. Recently, a similar reaction system was also developed for the transformation of HMF into FDCA in the presence of homogeneous catalysts [Co(OAc)2/Zn- (OAc)2/NaBr]. However, it is difficult to recycle homogeneous catalysts. Recently, heterogeneous catalysts have been widely utilized for chemical reactions. Among various heterogeneous catalysts, supported gold nanoparticles have been extensively used for the oxidation of HMF into FDCA. Although some of the reported methods produced high FDCA yields, some drawbacks were still present, including the high cost of the noble catalyst, high oxygen pressure, and use of base additives.

Extensive research on the hydrothermal conversion of organic waste and low-value organic materials into fuels and chemicals has demonstrated that hydrothermal reactions can convert various natural organic materials directly and efficiently into useful chemicals, synthetic organic materials like plastics into oil and ultra-heavy crude oil like bitumen into light oil. Some works on the hydrothermal conversion of biomass, the chemical reactions for specified compounds and the roles of HTW in chemical reactions have been described in review articles. Tester et al. reviewed hydrothermal technology for converting biomass into liquid and gaseous fuels, and Watanabe et al. reviewed chemical reactions for C1 compounds in sub- and supercritical water. Akiya and Savage reviewed the role of HTW in chemical reactions.

HTW exhibits properties that are very different from those of ambient liquid water. The ion product (Kw) at 250–300 C is about three orders of magnitude higher than that of ambient liquid water. The natural abundance of hydronium and hydroxide ions suggests that some acid- and base-catalyzed reactions may proceed easily in HTW without the addition of a catalyst. Research into the catalytic role of acids and bases in sub- and supercritical water has studied model acid/base catalyzed reactions, such as ether reactions, the hydrolyses of esters, the dehydration of alcohol and alkylation reactions. This section outlines the base catalytic role of HTW in the conversion of carbohydrates into lactic acid and the acid catalytic role in the conversion of carbohydrates into 5-hydroxymethyl2-furaldehyde (HMF).

Research into the acid catalytic role of HTW is more active than into the base catalytic role. Many studies have found that a large quantity of HMF, a product of the facile acid catalyzed dehydration of hexoses, is formed in the hydrothermal treatment of carbohydrates without addition of an acid catalyst. The formation of HMF may then be attributed to either an acid catalytic role of subcritical water or autocatalysis by acidic product formation. Experiments in the presence of formic and acetic acids, 500– 1000 ppm each, with the aim of recognizing the autocatalytic potential of formic and acetic acids showed that acetic and formic acids do not significantly catalyze the reaction. It has been suggested that HTW may act both as an acid and base catalyst. Experimental results give support to this thinking, as it has been shown that lactic acid is observed in experiments where 0.02 mol L1 H2SO4 is used, whereas HMF and 2-furaldehyde (2-FA) are observed when 0.02 mol L1 NaOH is used.

The examination of the effect of temperature on the yields of lactic acid and HMF show that the highest yields of both HMF and lactic acid are obtained in the temperature range of 280–300 C. High yields at these temperatures imply that the ionization constant has a strong influence on the reaction chemistry.

Generally, hexoses undergo dehydration to form HMF, whereas pentoses undergo dehydration to form 2-furaldehyde (2-FA). Many researchers have found, however, that 2-FA is formed during hydrothermal treatment of hexoses without the addition of catalyst. The mechanism of 2-FA formation from hexoses is unclear. One possible mechanism is that hexose is first degraded to HMF, which then loses a –CH2O group to form 2-FA. The second possible mechanism is that hexose is first degraded to pentose, which then forms 2-FA.

Luijkx et al. have reported that 2-FA can be formed from HMF in supercritical water. In our experiments with HMF at 400 C, the production of a small amount of 2-FA was observed. However, the production of 2-FA was not observed at 300 C. Furthermore, experiments at 300 C both without and with the addition of HMF to the solution after the hydrothermal reaction of glucose were performed to examine the possibility of intermediate products that might form in the hydrothermal treatment of glucose, but results showed that HMF produces minimal 2-FA. These results may indicate that formation of 2-FA via HMF does not readily proceed in subcritical water.

2. Chapter one: the selective oxidation of HMF to DFF.

1.Classification of catalysts:

A. Heterogeneous catalysis:

Serious study of heterogeneous catalysis has proceeded with ever-in- ^ creasing intensity for some 70 years; by contrast, serious study of homogeneous catalysis by transition metal salts and complexes began only a decade ago. It is scarcely surprising therefore that heterogeneous catalysis has achieved a cardinal position in chemical industry, whereas the application of homogeneous catalysis (although not slow to start) has yet to achieve a similar prominence. Among the considerations discussed in this volume is the question of whether homogeneous catalysis may in a generation have relegated many heterogeneous catalytic operations to the lumber-rooms of chemical technology.

Although heterogeneous catalysis has a good head start in its applications and usefulness because of its chronological advantage, theoretical understanding of its phenomena has not progressed as rapidly. It is no exaggeration that some homogeneously catalyzed reactions are understood as well after five years study as some heterogeneously catalyzed ones are after 50. The reasons for this are not hard to find: the application of modern physical methods (particularly spectroscopic ones) to detecting intermediates, and the simplicity and reproducibility of homogeneous systems, permits the specification of reaction mechanisms with a facility which is the envy of those who are restrained to multiphase systems. Those so restrained have hoped, not unreasonably, that the rapid advances we are witnessing in understanding homogeneous mechanisms will assist the resolution of some of the seemingly intractable problems in the heterogeneous field.

Heterogeneous Catalytic Properties of the Group VIII Metals In addition to their ability to atomize molecular hydrogen ( an ability widely shared by other d metals although not to the same extent by sp metals), the Group VIII metals are outstanding in their propensity to catalyze the hydrogénation of unsaturated functions, for example C=C , C=C , C=0 , C=N , NNN , 0=0 , N02 etc. Between the metals there are however considerable differences in activity, selectivity, and stereospecifity shown; thus, all the Group VIII metals catalyze the hydrogénation of oxygen, olefins, and acetylenes, while the facility to synthesize ammonia is limited to the Fe, Ru, Os Group. Hydrogenolysis of carbonhalogen bonds and, under more vigorous conditions, of C— C bonds is also catalyzed by these metals. A practical difficulty often encountered is the lack of specificity shown by heterogeneous catalysts; for example, supported palladium catalysts will convert a chloronitrobenzene to a mixture of chloroaniline and aniline, and undesirable selective poisoning procedures often must be adopted to obtain the desired result. Some of the Group VIII metals have uses as oxidation catalysts. A l l except platinum do however tend to oxidize under vigorous conditions, such as are used in ammonia oxidation and the Andrussow process, for which only platinum and its alloys are acceptable catalysts. Under milder conditions both platinum and palladium have somewhat limited applications in liquid-phase oxidation processes, as for example in the carbohydrate field.

B. Homogeneous catalysis:

The type of catalysis in which both the reactants and the catalyst are in the same phase with each other. Like if we have reactants in the gaseous phase, the catalyst which is to bring about the reaction is also in the gaseous state. That is they share the physical state with each other.

The main areas which have commanded attention to the present are olefin isomerization, hydrogénation, oxidation, carbonylation, and polymerization. Olefin isomerization has been widely studied, mainly because it is a convenient tool for unravelling basic mechanisms involved in the interaction of olefins with metal atoms. The reaction is catalyzed by cobalt hydrocarbonyl, iron pentacarbonyl, rhodium chloride, palladium chloride, the platinum-tin complex, and by several phosphine complexes; a review of this field has recently been published. Two types of mechanism have been visualized for this reaction. The first involves the preformation of a metal-hydrogen bond into which the olefin (probably already coordinated ) inserts itself with the formation of a σ-bonded alkyl radical. On abstraction of a hydrogen atom from a different carbon atom, an isomerized olefin results.

The ability of solutions of salts and complexes of the Group VIII metals to catalyze homogeneous hydrogénation is also widespread; once again hydridic species probably play an important role.

Among the complexes which may function in this way are pentacyanocobaltate ion, iron pentacarbonyl, the platinum-tin complex, and iridium and rhodium carbonyl phosphines. It has been suggested that with tristriphenylphosphine Rh(I) chloride, a dihydride is formed and that concerted addition of the two hydrogen atoms to the coordinated olefin occurs . There are few examples of the homogeneous reduction of other functional groups besides C=C , C=C , and C=C—C=C ; pentacyanocobaltate incidentally is specific in reducing diolefins to monoolefins. Among the several types of homogeneously catalyzed reactions, oxidation is perhaps the most relevant and applicable to chemical industry. The well-known Wacker oxidation of ethylene to ethylene oxide is the classic example, although this is not a true catalytic process since the palladium (II) ion becomes reduced to metallic palladium unless an oxygen carrier is present. Related to this is the commercial reaction of ethylene and acetic acid to form vinyl acetate, although the mechanism of this reaction does not seem to have yet been discussed publicly. Attempts to achieve selective oxidation of olefins or hydrocarbons heterogeneously do not seem very successful.

Unsaturated compounds have been carbonylated by their reaction with carbon monoxide under pressure in the presence of palladous chloride, but supported palladium catalysts will also perform this function. This is perhaps the clearest illustration of a class of reactions which proceeds both homogeneously and heterogeneously with apparent comparable facility. Rhodium chloride catalyzes the polymerization of butadiene with high stereospecificity to trans-poly( 1,4-butadiene) and also the dimerization of ethylene and other olefins . Although certain oligomerizations are catalyzed by solid palladium and rhodium catalysts, polymerization to high molecular weight products is not generally observed.

In one field, although restricted, there is a reasonably close analogy between the reactivity of olefins under reducing conditions in both homogeneous and heterogeneous catalytic systems. We now turn our attention to possible explanations of the observed anomalies and to the causes of the different behaviors shown by the two systems in oxidation and polymerization. The major anomaly in olefin reactions is the superior ability of Fe, Co, and N i to act as hydrogénation catalysts in comparison with expectations based on the strength of olefin bonding in complexes. Olefins are quite strongly chemisorbed by these metals; we must therefore infer that the presence of several metal atoms in proximity sometimes confers a binding ability not possessed by single atoms. Whether this effect is of particular importance with these metals or whether it will prove to have general significance is not certain at this time and will clearly be a matter for future debate. Structure determinations of organometallic complexes performed in recent years have vastly widened our concepts of chemical bonding, and of particular relevance to our problem are the recently investigated complexes of alkynes with multi atom clusters. It will be interesting to see whether such multi atom clusters have catalytic properties.

We now consider homogeneously catalyzed oxidation and polymerization—both of which do not have strict heterogeneous counterparts. Taking the Wacker oxidation of ethylene to acetaldehyde as an example, it appears that the central role of the Pd atom is to act as an electron acceptor, permitting the first formed (HOCH 2 C H 2 PdCl 3 ) 2 ~ species to form the HOCH 2 C H 2 + carbonium ion, which subsequently rearranges to CH 3 C H O and H + . The accumulation of negative charge on the PdCl 3 moiety is released only by disruption to Pd° and 3C1". Strict analogy in a heterogeneous system is therefore not to be expected since surface metal atoms cannot similarly be reduced, and some alternative means of releasing the negative charge would have to be found.

C. Noble metal catalysts:

Metals that are corrosion resistant and offer oxidation in moist are known as noble metal catalysts. Noble metals include platinum (Pt), Osmaium (Os), palladium (Pd), ruthenium (Ru), silver (Ag), iridium (Ir), and gold (Au).

All of the catalysts presently used for purification of automotive exhaust contain the noble metals Pt, Pd or Rh as active components. Because of the high cost and limited availability of these metals, it is important to use as low a noble metal concentration in these catalysts as feasible. This is accomplished by keeping the active metals at a high degree of dispersion. Two patents claimed that this can be achieved by adding a promoter such as Ce02. It is important, however, to understand the ways in which efforts to reduce the noble metal content of the catalysts affect catalytic activity. It is well known, for example, that the degree of dispersion, the nature of the catalyst support, and the presence of the promoter affect the specific catalyst activity, the selectivity, and the kinetic parameters. Furthermore, catalysts are routinely exposed to high temperatures of 600°C and above for varying periods of time. This thermal aging can cause severe sintering and decreased dispersion. Thus the kinetics of the reaction over an aged catalyst may be different from those of a fresh catalyst. We have made a detailed study of the kinetic parameters of the total oxidation of CO and the model hydrocarbons as a function of the following variables: (1) nature and concentration of noble metal, Pt, Pd, and Rh; (2) bulk metal versus supported catalysts; (3) degree of dispersion; (4) thermal aging; (5) presence of the promoter, CeO,; (6) effect of pretreatment; and (7) operating conditions, e.g., oxidizing or reducing.

The results for CO and olefin oxidation over the supported catalysts with or without CeOz are complex. The kinetic parameters suggest that there is more than one type of catalytic sites, each having a different set of kinetic parameters. For convenience, we call the kinetic behavior that closely resembles that obtained over the wire samples as type I kinetics. The conversion curves for this type of kinetics generally show the light-off phenomenon, a sharp rise in conversion from 20 to 100% within a very narrow range of temperature. The kinetics of CO and olefins oxidation over many low PM concentration catalysts, particularly those containing CeOz, differ sharply from those of the wires. In general, they are less inhibited by CO or hydrocarbon (over Pt or Pd) or by O2 (over Rh) and show a smaller partial reaction order with respect to the other reactant. The activation energies for CO oxidation are also much lower.

Comparison of the catalytic activity of the various catalysts can only be made among catalysts with approximately the same kinetic parameters. Among the PM/ A1203 catalysts exhibiting predominantly type I kinetics and for which the approximate surface areas are known, the rate of CO oxidation per unit PM surface areas varies within 0.2 to 0.6 of the value found for the respective wire. In view of the fact that the areas of the wires are underestimated (the geometrical area without correction for the roughness was used) and the large range of metal dispersions covered in the results, the specific rate of CO oxidation can be considered to be independent of the presence of the A&O3 support. The specific oxidation rates of C3H6 over the type I sites of the PM/A1203 catalysts are at least one order of magnitude lower than those over the PM wire. This may be rationalized by the size effect, i.e., C3H6 is a larger molecule than CO and may require several adjacent sites for adsorption, thus not all the surface metal sites are usable for C3H6 oxidation.

D. Transition metal catalysts

Transition metals and their compounds function as catalysts either because of their ability to change oxidation state or, in the case of the metals, to adsorb other substances on to their surface and activate them in the process.

Ziegler-Natta (Z-N) and metallocene-alumoxane type catalyst systems for the polymerization of olefins are well known in the art. Recently a new, ionic pair type of catalyst has been developed which yields polymers of improved properties compared to those made with conventional type catalysts systems. It discloses new cyclopentadienyl based catalyst systems comprising an ionic compound wherein the cyclopentadienyl transition metal component or metallocene is reacted with an activator comprising an anion and a cation; the cation being one which is reactable with a non-cyclopentadienyl ligand of the cyclopentadienyl moiety to yield as the reaction product a neutral ligand derivative, and a cationic metallocene species to which the anion of the activator compound is essentially non-coordinating.

This invention relates to new poly anionic non-coordinating anions or activator moieties comprising a plurality of metal or metalloid atom-containing non-coordinating anionic groups pendant from and chemically bonded to a core component, which can be used to prepare a wide variety of new ionic catalysts compositions which are useful in the polymerization of olefins, di olefins and/or acetyl enically unsaturated monomers. These non-coordinating anions are stabilized by a sufficient number of cations to balance charge on the composition or catalyst formed. When exposed to unsaturated monomers, the polymerization catalyst of this invention yield a wide variety of homo or copolymers having variable molecular weight, molecular weight distribution and comonomer content.

In one application, the poly anionic activators are used to prepare a catalyst system of enhanced performance by immobilizing the catalyst on a catalyst support material. The heterogeneous, or supported, catalyst of this invention can be used in a wide variety of commercial processes including gas phase, slurry or fixed bed reactors.

Catalytic oxidation of HMF to DFF

Selective oxidation of 5-hydroxymethyl-2-furfural (HMF) to 2,5-diformylfuran (DFF) toward industrial production was studied over Ru supported g-alumina catalyst using molecular oxygen as an oxidant. From the solvents screening, considering recyclability after reaction, toluene was found to be the best solvent and gave maximum conversion of 99% with 97% DFF selectivity at 130 8C and 40 psi O2 pressure. Catalyst was washed with NaOH solution of pH = 12 to remove the adsorbed polymer impurities and then reused up to 5 cycles. The product could be purified by simple evaporation of the solvent, which could add advantage for industrial process.

DFF is among highly potential chemicals which can be applied to furanic polymers, a precursor for pharmaceuticals and antifungal agents, and renewable furan-urea resin. In addition, DFF is a readily handled intermediate of FDCA known as a promising alternative to petroleum-based terephthalic acid (TPA) owing to its poor solubility in most of the organic solvents which renders its application. Several attempts were made to prepare DFF in one step from fructose (one of the biomass-derived carbohydrates) using both homogeneous and heterogeneous catalysts in aprotic polar solvents like DMSO and DMF. However, high boiling points of those solvents have caused the difficulty in isolation of DFF and reuse of solvents. Therefore, selective oxidation of HMF to DFF was preferably explored with a range of oxidizing agents and solvent system. Homogenous metal bromide catalyst (MBr2, M = Co(II)/Mn(II)/Zr(II)) in acetic acid solvent at 70 bar oxygen pressure gave 99.7% of HMF conversion with 61% of DFF selectivity. Oxidation of HMF in water solvent always led to carboxylic acid byproducts which are difficult to separate from DFF. Due to strong oxidative power in water. Homogenous Mn(III) salen complexes gave maximum of 86% DFF yield in buffer–CH2Cl2 system in room temperature using NaOCl as an oxidant and this system found difficulty in reusability. Vanadyl-pyridine complexes (PVP) in homogeneous reaction in DMSO solvent gave 81% conversion with >99% DFF selectivity, however SBA supported vanadyl-pyridine complexes (PVP) gave only 50% conversion with 98% DFF selectivity in 10 bar air pressure. With this regard, the selective oxidation of HMF under recyclable solvent system is still challenging particularly in industrial area.

100 mL of 0.5 mM solution of RuCl3 was taken to which 2 g of gAl2O3 (350–500 mm) was added and stirred at room temperature for 3 h. Filtered and washed with copious amount of water and dried in vacuum oven at 30 8C. All the reactions were carried out in a 50 mL Parr reactor; HMF, solvent, and catalyst were added and reactor was flushed with O2 for 3 times. Pressurized with O2 again and heated up to the desired temperature, the operating pressure was maintained at 40 psi (unless otherwise mentioned); all the reactions were carried for 4 h with 650 rpm stirring. Immediately after the reaction reactor was cooled to room temperature and samples were analyzed with HPLC (Agilent Technologies 1200 series) using 0.001 N H2SO4 buffer and Bio-Rad Aminex HPX-87 H (300 mm 7.8 mm) column.

Powder X-ray diffraction analysis of g-Al2O3 and Ru/g-Al2O3 materials showed that the crystalline nature of the material is slightly increased during ruthenium loading. There are no distinct reflections for the Ru (0) or RuO2 was observed and Ru/g-Al2O3 has the BET surface area of 101 m2 /g. ICP analysis of the samples showed that 1.8 wt% of Ru was supported in g-Al2O3. For screening most suitable reaction media for selective oxidation of HMF, solvent variation studies were performed with a range of readily recyclable solvents with moderate boiling points using Ru/g-Al2O3 at a constant pressure of 40 psi.

Great selectivity toward DFF was shown in alcohol-type solvents including ethanol, 1-butanol, and IPA showed (99%), however, conversion was unsatisfactory (18% in ethanol, 3% in 1- butanol, 40% in IPA). Low boiling point aprotic acetonitrile also gave low conversion of HMF less than 30% though it showed 99% DFF selectivity. DMF and MIBK gave a modest level of conversion (35% in DMF and 44% in MIBK), and on the other hand they also gave FFCA as an over-oxidation product and LA as a deformylated product by along with DFF. The highest oxidation power occurred in water and FDCA that is most oxidized product of HMF was obtained as a major product (24% in selectivity). Good HMF conversion of 88% with DFF selectivity of 40% appeared using 1,4- dioxane as a solvent and it was however observed that (through GCMS) decomposition of 1,4- dioxane took place under this reaction conditions, which led to several decomposed products. Attempts were made to overcome decomposition of 1,4-dioxane by low temperature and low pressure but failed to obtain good conversion. Non-polar toluene showed HMF conversion of 93% with DFF selectivity of 98% that is the highest conversion reported for readily recyclable solvents with a moderate boiling point.

Further to improve the yield of DFF in toluene, optimization of reaction temperature and substrate concentration were carried out. As expected, HMF conversion decreased for low temperature reactions. HMF conversion was less than 70% at 80 8C but 99% HMF conversion could be achieved at 130 8C within 4 h. The DFF selectivity was >97% in all different temperatures and this result was the uniqueness of the toluene solvent.

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focusonthegoodnews · 3 years

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Scientists develop method to recycle plastic bottles into aviation fuel using less energy

Good News Notes: “Humans produce more than 6 billion tons of plastic every year, and its accumulation in landfills and oceans is considered by many to be an environmental crisis. Only 9% of plastics are recycled in the U.S., and while bans on single-use plastic bags and straws have some benefits, we’re nowhere near addressing the volume of tossed plastic bottles and containers, toys, furniture…

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adambrown275 · 2 years

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Tertiary Butylamine (CAS 75-64-9): A Comprehensive Overview

Summary – Tertiary Butylamine is an intermediate for manufacturing a range of products. Learn about its preparation technique and applications.

Tert.-Butylamine is primarily an aliphatic amine. Its application is for producing accelerators in the rubber industry. However, you can also use it in your agricultural and pharmaceutical industries. Look for reliable manufacturers to buy Tertiary Butylamine. Make sure that the purity level of the chemical is at least 99.5%. You may purchase Tert.-Butylamine in bulk.

What are the applications of Tert.-Butylamine?

Tertiary Butylamine is useful in different ways. You can use it as an effective solvent to remove capping agents (like KBr) and surfactants (PVP) from nanoparticle surfaces. A combination of amino acid, TBA, and platinum can trigger anti-tumor activities. The aziridination of some components (such as 2-aryl ethenyl(diphenyl)sulfonium salt) needs a base. You can choose Tertiary Butylamine for this purpose. It helps in the creation of the N-tert-butylaziridine.

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How do you identify Tertiary Butylamine?

The Molecular formula of the chemical compound is C4H11N. Tertiary butylamine, also known as TB Amine is a colorless and clear liquid substance. You can smell an ammonia-like odor. Butane has 4 isomeric amines, and Tertiary butylamine is one of them. The boiling point of TB Amine ranges from 43 to 47 ° C. The vapor density is 2.5 (Air=1), while the density is 0.696 g/mL. So, you must know about these properties before using Tertiary Butylamine 75-64-9 for your industrial purposes.

Soluble in chloroform, this liquid needs to be handled carefully because it is flammable. You can also blend it with water, ether, and alcohol. Tertiary butylamine remains in the best condition for 24 months. You must store it at room temperature.

What is the way of manufacturing tert Butylamine?

Isobutylene undergoes a direct amination process to turn out Tertiary Butylamine. The process is acceptable in almost every commercial sector. In the case of the small-scale production process, 2,2-dimethylethylenimine hydrogenolysis helps in making TB Amine. Another process chosen by manufacturers is a combination of sulfuric acid with isobutylene. Then, hydrogen cyanide is added to it to generate tertiary butylformamide. The hydrolysis process is effective in yielding Tertiary butylamine.

You can buy Tertiary butylamine in packs of different sizes, ranging from 100mL to 1 L. So, you may place your order based on your needs. A bulk purchase will make your deal cost-effective.

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marketrevenueba · 3 years

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Fatty Alcohols Market Overview,Size, Share, Industry Analysis and Global Forecast to 2028

Reports and Data’s latest study titled ‘Global Fatty Alcohols Market’ is an in-depth analysis of the global Fatty Alcohols industry and studies each industry segment in detail. The market intelligence report makes accurate estimations of the Fatty Alcohols market’s future growth potential. It provides the reader with a clear description of the market’s future growth prospects and upcoming trends. The report includes quantitative and qualitative analyses of the Fatty Alcohols market and the key aspects of the market, such as the product portfolios, pricing structure, industry trends, end-user industries, sales statistics, distribution channels, and top manufacturers. The report offers a closer view of the key market dynamics including market growth drivers, threats, opportunities, and challenges. A thorough study of the key business strategies, demand and supply ratios, leading market regions, and the established and new market players in a pivotal component of the report.

The developmental scope of the new entrants and established companies of the Fatty Alcohols market has been highlighted in the report. Also, the market positions of these companies have been evaluated using cutting-edge analytical tools such as Porter’s Five Forces Analysis, SWOT analysis, and investment assessment. The latest report throws light on the gross profits, revenue shares, individual growth rate, sales volume, manufacturing costs, and financial positions of the key market players. Another key component of the global Fatty Alcohols industry report is the COVID-19 section that deeply analyzes the present global health crisis and its disruptive effects on the global economy and, particularly, this industry. Hence, the Fatty Alcohols industry growth is severely hampered due to the economically damaging impact of the COVID-19 pandemic. Thus, the Fatty Alcohols market report is aimed at helping readers gain actionable insights into this industry.

The global fatty alcohol market is forecast to reach USD 7,815.4 Million by 2028, according to a new report by Reports and Data. Fatty alcohols can be defined as, usually, straight-chain, high-molecular-weight, primary alcohols. However, these alcohols can range from as less as 4–6 carbons to as many as 22–26 carbons, which are usually derived from natural oils and fats. There are various advantages associated with these alcohols, which are contributing to the growth of the market. In this regard, one of its mentionable feature is unusual surface-active properties, due to which, this product witnessed sizable consumption along with extensive commercial use in synthetic detergents. Two of the commercially used methods for reduction associated with manufacturing these alcohols are hydrogenolysis of either fatty acids or fats and sodium reaction.

Leading Market Competitors:

AkzoNobel, BASF, Cargill, Emery Oleochemicals, Solazyme, Wilmar International, Archer Daniels, Midland, Evonik Industries, China Sanjiang Fine Chemicals, and Kao Chemicals.

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Growth Prospects:

The packaging sector has been attempting to gain momentum in the past couple of years on the back of the massive boom of the e-commerce industry. The market growth will be credited to the e-commerce transport and shipment, personal care, household, food and beverage, and healthcare sectors for convenience packaging.

These aspects have pushed leading players to dedicate their resources towards new packaging designs or to reinvent existing packaging designs to accommodate higher convenience and manageability, which will drive the global Fatty Alcohols market growth. The vintage packaging sector is also experiencing high demand, and even though it targets a limited consumer base, it is expected to grow at a rapid pace in the coming years.

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Global Fatty Alcoholss Market Segmentation:

Based on Product Type:

C15-C22 Fatty Alcoholss

C11-C14 Fatty Alcoholss

C6-C10 Fatty Alcoholss

Based on Application:

Personal care

Soaps & detergents

Amines

Lubricants

Others

Key market trends:

The increasing prevalence of biodegradable plastics promises to be a popular trend dominating the industry in the forecast years. The growing environmental awareness and the stringent government-imposed regulations for governing the consumption of plastics are pushing the overall industry towards the use of biodegradable packaging.

Another major packaging market trend that is speedily gaining momentum is the introduction of innovative lightweight glass packaging aimed at improving end-user usability and waste reduction. These packaging designs offer recyclability, easy transportability, and cost-effectiveness, which has urged manufacturers to produce water-resistant and eco-friendly corrugated box packaging solutions.

Another significant packaging market trend quickly gaining momentum is the development of new lightweight glass packaging to improve end-user usability and reduce wastage. These packaging designs are recyclable, economical, and easy-to-transport, urging manufacturers to produce water-resistant, eco-friendly, and smart corrugated packaging technology.

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Regional Analysis covers:

North America

Europe

Asia Pacific

Latin America

Middle East & Africa

About Reports and Data

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synopsischemitech · 3 years

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Chemical Technologies

The Chemical Technology of Wood is an eight-chapter introductory text on the developments in understanding the chemistry of wood and its chemical-technological utilization. The opening chapters of this book cover the productive aspects of forests, followed by a description of the anatomy and physical properties of wood. The subsequent chapter presents a summative wood analysis concerning its cellulose, hemicelluloses, lignin, and other extraneous components. This topic is followed by a presentation of several destructive processing of wood, including acid hydrolysis, pyrolysis, oxidation, and hydrogenolysis. The remaining chapters describe pulp production through sulfite cooking and using alkaline reagents. This book will prove useful to chemists, engineers, biologists, foresters, and economists.

This is a real shame because the world as we know it wouldn’t exist without chemistry. Here are my top five chemistry technology inventions that make the world you live in.

Penicillin

There’s a good chance that penicillin has saved your life. Without it, a prick from a thorn or sore throat can easily turn fatal. Alexander Fleming generally gets the credit for penicillin when, in 1928, he famously observed how a mold growing on his Petri dishes suppressed the growth of nearby bacteria. But, despite his best efforts, he failed to extract any usable penicillin. Fleming gave up and the story of penicillin took a 10-year hiatus. Until 1939, it took Australian pharmacologist Howard Florey and his team of chemists to figure out a way of purifying penicillin in useable quantities.

The Haber-Bosch process

Nitrogen plays a critical role in the biochemistry of every living thing. It is also the most common gas in our atmosphere. But nitrogen gas doesn’t like reacting very much, which means that plants and animals can’t extract it from the air. Consequently, a major limiting factor in agriculture has been the availability of nitrogen.

Polythene – the accidental invention

Most common plastic objects, from water pipes to food packaging and hardhats, are forms of polythene. The 80m tons of the stuff that is made each year is the result of two accidental discoveries.

The Pill and the Mexican yam

In, the 1930s physicians understood the potential for hormone-based therapies to treat cancers, menstrual disorders, and of course, contraception. But research and treatments were held back by massively time-consuming and inefficient methods for synthesizing hormones. Back then progesterone cost the equivalent (in today’s prices) of $1,000 per gram while now the same amount can be bought for just a few dollars.

The screen you are reading on

Incredibly, plans for flat screen color displays date back to the late 1960s! When the British Ministry of Defense decided it wanted flat screens to replace bulky and expensive cathode ray tubes in its military vehicles. It settled on an idea based on liquid crystals. It was already known that liquid crystal displays (LCDs) where possible, the problem was that they only really worked at high temperatures. So not much good unless you are sitting in an oven.

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duplexplate · 4 years

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Corrosion properties of duplex stainless steel S32205 plate

It is stainless steel that contains about a 25% increase in chromium (Cr), about 5% decrease in nickel, and a 1:1 two-phase mixture of austenite and ferrite.

It features high strength and high corrosion resistance and is also excellent in stress corrosion cracking. Therefore, it is used in a wide range of applications such as sluices, tunnels, sewer facilities, seawater desalination plants, and chemical tankers.

Duplex Plate is widely used in industries and components such as steelmaking, papermaking, desalination equipment, firewalls, bridges, pressure vessels, heat exchangers, turbine blades, and for transmission shafts for marine systems.

The higher the content of chromium, molybdenum and nitrogen alloying, the better corrosion resistance property Duplex 2205 Plate has. When duplex stainless steel contains at least 30% ferrite in the microstructure, its corrosion resistance is much better than that of austenitic stainless steel. However, because ferrite is sensitive to hydrogen embrittlement, duplex stainless steel 2205 does not currently have high corrosion resistance in environments and applications where hydrogen penetrates the metal and causes hydrogen embrittlement.

Pitting corrosion resistance

In specific chloride environments, each grade of stainless steel can be described by its critical point corrosion temperature (CPT), above which pitting corrosion begins to occur and grows to the naked eye within 24 hours. There is a possibility that Super Duplex Plate have less corrosion resistance below the required temperature. It represents a particular stainless steel grade and the environment.

Grain boundary corrosion resistance

Intergranular corrosion often appears in joint gaskets, bottom sediments, and bolt joints. There is a similar critical temperature for intergranular corrosion. The critical crevice corrosion temperature (CCT), is mainly depends on the stainless steel specimen, chloride environment, and crevice properties (compactness, length, etc.). Due to the shape of the gap and the fact that it is challenging to present the same gap size in practice, the CCT measurement data is more diversified than the critical point corrosion temperature (CPT). CCTS tends to be 15-20°C lower than CPT for the same grade and corrosive environment.

Stress corrosion resistance

Like many materials, Duplex Steel Sheet are susceptible to stress corrosion cracking under certain conditions. This can occur at elevated temperatures, in chloride-containing environments, or media sensitive to hydrogenolysis. In Environmental conditions stress corrosion cracking can occur in duplex stainless steel plates.

Tests have demonstrated superior corrosion resistance compared to austenitic and ferritic stainless steels. The sample of plates used for the 2205 stainless steel test has a size of 1600 * 2500 * 10mm, supplying a wide range of metals for different applications.

The key to the duplex stainless steel welding material is the extremely high N content. In welding of Duplex Steel Plate, porosity defects such as blowholes, pits and gas grooves due to N are more likely to occur than in general austenitic stainless steel. When welding duplex stainless steels, it is basically recommended to select welding materials of the same grade and, in some cases, of higher grades.

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chemwhat · 4 years

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Palladium CAS#: 7440-05-3

IdentificationPhysical DataSpectraRoute of Synthesis (ROS)Safety and HazardsOther Data

Identification

Product NamePalladiumIUPAC NamepalladiumMolecular Structure

CAS Registry Number 7440-05-3EINECS Number231-115-6MDL NumberMFCD03457879Synonymspalladium, palladium on carbon, palladium atom, palladium(0), palladium,, palladiun, Palladium; 7440-05-3; CAS Number 7440-05-3; CAS NO 7440-05-3Molecular FormulaPdMolecular Weight106.42InChIInChI=1S/PdInChI KeyKDLHZDBZIXYQEI-UHFFFAOYSA-NCanonical SMILES Patent InformationPatent IDTitlePublication DateUS2013/300039--1,4-DIAZA-SPIROUNDECANE-5-ONE DIMALEATE, USE THEREOF AS A MEDICAMENT AND METHOD FOR THE PRODUCTION THEREOF2013US2013/79412Branched 3-phenylpropionic acid derivatives and their use2013US2013/851286-(4-HYDROXY-PHENYL)-3-ALKYL-1H-PYRAZOLOPYRIDINE-4-CARBOXYLIC ACID AMIDE DERIVATIVES AS KINASE INHIBITORS2013

Physical Data

AppearanceWet black powderMelting Point1,554.69 °C (2,830.44 °F) Resistivity9.96 μΩ-cm, 20°C Boiling Point, °C Pressure (Boiling Point), Torr220075025407503000 - 33007503980750 Density, g·cm-3Measurement Temperature, °C12.053527.21219.8511.9920 Refractive IndexWavelength (Refractive Index), nmComment (Refractive Index)1.65 - 3.4600depending on the thickness of Pd layer1.62579

Spectra

Description (NMR Spectroscopy)Nucleus (NMR Spectroscopy)Solvents (NMR Spectroscopy)Temperature (NMR Spectroscopy), °C Comment (NMR Spectroscopy)Spectrum2Dneat (no solvent, solid phase)SpectrumothersolidSignals givenSpectrum, Linewidth of NMR absorption105Pdsolid matrix-268.95 - 26.85 Description (IR Spectroscopy)Solvent (IR Spectroscopy)Comment (IR Spectroscopy) Bandsneat (no solvent, solid phase)500 cm**-1 - 4000 cm**-1Spectrumneat (no solvent, solid phase) 1900 cm**-1 - 2200 cm**-1Spectrumneat (no solvent, solid phase) 690 cm**-1 - 4000 cm**-1 Description (UV/VIS Spectroscopy)Solvent (UV/VIS Spectroscopy)Comment (UV/VIS Spectroscopy)Spectrum, Band assignmentwater600 nm - 1500 nmSpectrum, Band assignmentethane-1,2-diol250 nm - 550 nmSpectrumsolid400 nm - 1000 nmSpectrum, Band assignmentisopropyl alcohol200 nm - 1200 nmSpectrum, Band assignmentdimethylformamide450 nm - 750 nm

Route of Synthesis (ROS)

Route of Synthesis (ROS) of Palladium CAS 7440-05-3 ConditionsYieldWith hydrazine hydrate In methanol cellulose (5 g) added to soln. of PdCl2 (0.443 g) in MeOH; stirred (15 min); 80% hydrazine hydrate added dropwise (15 min); stirred (12 h, room temp.); solid filtered; washed with methanol and acetone; dried (vac.);99%With hydrogenchloride; hydrazine In water98%With formic acid In not given refluxing a soln. of PdCl2 and HCOOH for 30 min; decantation, washing with water, drying for 2 h at 120°C;96%With perchloric acid; 2,4-dichlorophenol; phosphododecatungstate In water Kinetics; Irradiation (UV/VIS); irradiated (>320 nm) at pH 1 (HClO4) at 18.3°C for 150 min; ppt. collected, dried, elem. anal.;83%With 2,3,5,6-tetramethyl-1,4-bis(trimethylsilyl)-1,4-diaza-2,5-cyclo-hexadiene In tetrahydrofuran at 20℃; for 12h; Inert atmosphere; Toa THFsuspension (5.0 mL) of 89 mg (0.50 mmol) of brownpalladium (II) chloride prepared in a Schlenk tube under an argonatmosphere was added 141mg (0.50 mmol) of Me4BTDP in THF The solution (5.0 mL) was added dropwise at room temperature.It quickly became a black suspension.After 12 hours, stirring was stopped and the mixture was allowed to stand to precipitate a black solid.The brown supernatant was filtered off and the resulting precipitate was washed three times with 5.0 mL of THF.The solid after washing was dried to obtain 27 mg of black palladium powder (0.25 mmol, yield 50%). 50%

Safety and Hazards

Pictogram(s)

SignalDangerGHS Hazard StatementsH228: Flammable solid H315: Causes skin irritation H319: Causes serious eye irritation H335: May cause respiratory irritation H413: May cause long lasting harmful effects to aquatic life Information may vary between notifications depending on impurities, additives, and other factors. Precautionary Statement Codes P210, P240, P241, P261, P264, P271, P273, P280, P302+P352, P304+P340, P305+P351+P338, P312, P321, P332+P313, P337+P313, P362, P370+P378, P403+P233, P405, and P501 (The corresponding statement to each P-code can be found at the GHS Classification page.)

Other Data

TransportationNot dangerous goodsUnder the room temperature and away from lightHS Code381512StorageUnder the room temperature and away from lightShelf Life2 yearsMarket PriceUSD 2390/kg Use PatternThe product can be used as catalyst for; • hydrogenation of alkenes, alkynes, ketones, nitriles, imines, azides, nitro groups, benzenoid and heterocyclic aromatics; • hydrogenolysis of cyclopropanes, benzyl derivatives, epoxides, hydrazines, and halides; • dehydrogenate aromatics and deformylate aldehydes. Catalyst for: • Stille reaction • Hydrogenation reactions • Suzuki-Miyaura cross-coupling and Heck-Mizoroki reactions • Deoxygenation • Oxidation reactions • Coupling reactions Read the full article

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omc-juniperpublishers · 5 years

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Novel Route for Synthesis of Anti - Hyperglycaemic Activity of Thiazolidine 2,4- Dione Derivatives As A Mannich Bases-JuniperPublishers

Journal of Chemistry-JuniperPublishers

Abstract

The mannish bases of Thiozolidine 2,4 -dione derivatives has come to lime light due to their multi functional biological activities. Thiazolidine- 2,4- dione is an extensively explored hetero cyclic nucleus for designing of novel agents implicated for a wide variety of pathophysiological conditions, that is, diabetes, diabetic complications ,cancer, arthritis, inflammation, microbial infection, and melanoma. Present work, synthesise quinoline attached imidozoline derivative using (3 +2) cycloaddition via imine of quinoline and TOSMIC. These derivatives were converted to mannich bases of thiozolidine 2,4 one using knoevenagel condensation. The sulfonyl derivatives of thiozolidine 2, 4 -dione were also synthesized and characterized by using alkylation conditions.

Keywords: Imidazole derivatives; Thiozolidine 2,4 one nucleus; TOSMIC; Combi- flash Chromatography

Introduction

Thiazolidine 2,4 dione (TZD) is a vital nucleolus in heterocyclic chemistry. TZD shows multidirectional phamocodynamical activities such as Anti-hyperglycemic (glitazone drugs), anti-cancer, anti microbial, anti-arthritic. Due to multidirectional pathological actions, huge explored research work has been attempted and still efforts under progress for drug candidates. The metabolic disorder of diabetic is now a day's shows major impact on human beings throughout world. The Thiazolidine 2,4-dione (TZD) derivatives act as a drug candidates such as rosiglitagone, pioglitazone, lobigli tazone, enaglitazone, netoglitazone, ozoline, daragletazone, troglitazone etc. TZD derivatives not only confine for treatment of metabolic disorder diabetic, it o shows as an inflammatory agents, and anti- cancer and for treatment of melanoma. Due to importance of TZD, derivatives many scientists have been developed various routes for synthesis. Om silakari et al. developed different TZD derivatives and evolutes their biological activity (Figure 1). Ivanildo Mangueira, da Silva and co workers [1] developed TZD derivatives using Knoevenagel condensation (Figure 2). Boja Poojary and co workers [2] synthesized and characterization of Antimicrobial activity of novel derivatives (Figure 3). Archana Kapoor and Neha Khare [3] synthesized various mannich bases of Antibacterial and antifungal activity of 2,4-thiazolidinedione and rhodanine (Figure 4). Many routes has been developed for synthesis of 2,4thiozolidinone. The Thiazolidine 2,4 dione having many active sites. Thiazolidine 2,4,dione nucleus numbering is given as fallows (Figure 5).

Materials and Methods

All reagents and starting material were procured from commercial sources (Aldrich, Alfa Aesar). Solvents were thoroughly dried before use. THF and toluene were dried using sodium metal and benzophenone.DMF was dried using CaH. The new compounds were fully characterized using Analytical methods like IR, NMR (Bruker). The melting points were recorded using on a (WRS-1A) Digital Melting Point Apparatus without correction. Infrared spectra were taken using an AVATAR 370 FT-IR spectrometer. HNMR, CNMR spectra were recorded with a Bruker spectrometer operating at 400MHz used as a Trimethyl silane reference and values recorded in ppm. The progress of reaction was monitored using TLC system and I2 spray and KMnO4 TLC strain. The crude compounds were purified using column chromatography (100-200 mesh silica) and Combi-flash chromatography. The hydrogenolysis process was carried out using parr shaker [4-19].

Objective of this Research

lated to develop new synthetic route for preparation of the quinoline containing thiozolidin-4- one attached 1,3, 4 oxa diazole nucleus and thiazolidin-4-one attached benz imidazole and benz thiozole and benzoxazole derivatives and thoroughly characterized. The scaffolds of 2-(8-((5-(4- substituted phenyl)-1,3,4-oxadiazol-2-yl)methoxy) quinolin-5-yl)-3-(4-(trifluoromethyl)phenyl)thiazolidin-4- one(7a-h)weresynthesized and characterized.

Experimental Methods

In this research work, we prepared below compounds and mentioned in step wise manner

a) Step-1: (Z)-N-((8-(benzyloxy)quinolin-5-yl)methylene)-4- (trifluoromethyl)aniline (2)

b) Step-2: 8-(benzyloxy)-5-(1-(4-(trifluoromethyl) phenyl)- 1H-imidazol-5-yl) quinoline (3).

c) Step-3: 5-(1-(4-(trifluoromethyl) phenyl)-1H-imidazol-5- yl) quinolin-8-ol (4).

d) Step-4: 2-((5-(1-(4-(trifluoromethyl) phenyl)-1H-imidazol- 5-yl) quinolin-8-yl) oxy) acetaldehyde (5).

e) Step-5: 5-(5-(1-(4-(trifluoromethyl)phenyl)-1H-imidazol- 5-yl)quinolin-8-oxy)methylene)thiazolidine-2,4-dione (6).

f) Step-6: 3-(Amine substituted methyl)-5-(2-((5-(1-(4- (trifluoromethyl) phenyl]-1H-imidazol-5-yl]quinolin-8-yl]oxy] ethylidene)thiazolidine-2,4-dione (7a-f).

g) Step-7: 3-(sulfonyl-derivatives)-5-(2-((5-(1-(4-(trifluoromethyl) phenyl)-1H-imidazol-5-yl) quinolin-8-yl)oxy)ethylidene)thiazolidine-2,4-dione (8a-f) (Figure 6).

Reaction mechanism for Step 2 (Figure 7)

Step 1: (Z)-N-((8-(benzyloxy) quinolin-5-yl) methylene)-4-(trifluoromethyl) aniline(2)

p class="indent">8-(benzyloxy) quinoline-5-carbaldehyde (10 g, 0.038 mol),4-(trifluoromethyl] aniline (6.5 g, 0.039 mol] in dry toluene ( 100 mL) was added freshly dried molecular sieves and refluxed for 10 h under N

atm. The progress of reaction was monitored by TLC. After completion of starting material, toluene was evaporated under vacuum to gave crude residue of Compound- 2 (15 g) as a solid ( white colour). The crude was carried to next step (

Figure 8

Step 2 : 8-(benzyloxy)-5-(1-(4-(trifluoromethyl) phenyl)-1H-imidazol-5-yl)quinoline(3)

(Z)-N-((8-(benzyloxy) quinolin-5-yl)methylene)-4-(trifluoromethyl) aniline(2) (15 g, 0.036 mol)was dissolved in Dry DMF (80 mL) and cooled to O °C. To that dried K2CO3 (15 g. 108 mol) and Toluene methyl isocyanide (7.02 g, 0.036 mol) was added and warm to room temperature and stirred for 16h. The progress of reaction was monitored by TLC. After completion, reaction mixture was poured in ice cold water (100 mL) and extracted with EtOAc ( 3 x 100 mL). The organic layer was separated and washed with brine solution, dried over anhydrous Na2SO4, filtered and evaporated under vacuum to give crude residue. The obtained crude product was purified by column chromatography (100-200 mesh silica, Eluent: 80% EtOAc-Pet Ether) isolated 8-(benzyloxy)-5-(1-(4-(trifluoromethyl) phenyl)- 1H-imidazol-5-yl)quinoline(3) (10 g, yield: 64%) as a solid (Pale yellow colour). M.p. 252-255 °C. IR (KBr, cm-1): 3030, 1440, 1520, 1005, 691, 655. HNMR (d6-DMSO, 400 mHz): 5.2 (s, 1H, -CH2), 7.1 (m, 3H), 7.3-7.5 (m, 7H), 7.6-7.7 (m, 4H), 7.85(d, 1H), 8.36(d, 1H), 8.85(d, 1H ) (Figure 9).

Step 3 : 5-(1-(4-(trifluoromethyl)phenyl)-1H-imidazol- 5-yl)quinolin-8-ol (4)

8-(benzyloxy)-5-(1-(4-(trifluoromethyl)phenyl)-1H- imidazol-5-yl)quinoline(3) (10 g, 0.022 mol ) in MeOH (100 mL) was added 5% Palladium hydroxide on carbon (1 g, cat) and hydrozinated at 70 Psi under parr shaker for 3 h at room temperature. The progress of reaction was monitored by TLC. After completion, reaction mixture was filtered on cellite bed and thoroughly washed with MeOH (2 x 75 mL). The MeOH layer were collected and evaperated under vaccum to gave 5-(1-(4-(trifluoromethyl)phenyl)-1H-imidazol-5-yl)quinolin-8- ol (4)(7g, yield : 86%) as a solid (white colour)). M.p. 280-285 °C. IR (KBr, cm-1): 3620, 3014, , 1525, 1050, 691, 620 .1HNMR ( d6-DMSO, 400 mHz) : 6.5 (brs, 1H),7.1 (m, 2H), 7.3 (d, 2H), 7.63 (m, 4H),7.8(d,1H), 8.35(d, 1H), 8.8(d, 1H) (Figure 10).

Step 4 : 2-((5-(1-(4-(trifluoromethyl)phenyl)-1H- imidazol-5-yl)quinolin-8-l)oxy)acetaldehyde (5)

5-(1-(4-(trifluoromethyl) phenyl)-1H-imidazol-5-yl) quinolin-8-ol (4) (7 g, 0.017 mol) in Dry DMF (70 mL) was added K2CO3 (9.7 g, 0.07 mol, 4 eq) and stirred at rt for 30 min. To that a solution of 2-bromo-1,1-dimethoxy ethane( 1.2 eq) in DMF (20 mL) was added drop wise at 0°C and stirred for 5h. The progress of reaction was monitored by TLC. After completion, reaction mixture was filtered on cellite bed and washed with DMF (10 mL). The Reaction mixture was poured in ice cold water (200 mL) and stirred for 20 min. The reaction mixture was acidified aq NaHSO3 solution up to PH-5 and extracted with EtOAc (2 x 200 mL). The aqueous layer was collected and basified up to PH-8 with sat aq NaHCO3 sol. The aqueous layer was extracted with EtOAc (3 x 100 mL). The organic layer were collected and dried over anhydrous Na2SO4, filtered and evaporated under vacuum to gave 2-((5-(1-(4-(trifluoromethyl)phenyl)-1H-imidazol-5- yl)quinolin-8-yl)oxy) acetaldehyde (5) (5g) as a solid( white colour). M.p. 200-205 °C. IR (KBr, cm-1): 3602, 3014, 1712, 1646, 1503, 1050, 691, 644.1HNMR (d6-DMSO, 400 mHz) : 5.2 (s, 2H), 7.1 (m, 2H), 7.3(d, 2H),7.9(d, 1H), 8.36(d, 1H), 8.82(d, 1H), 9.6(s, 1H) (Figure 11).

Step 5: 5-(2-((5-(1-(4-(trifluoromethyl)phenyl)- 1H-imidazol-5-yl)quinolin-8-yl)oxy) ethylidene) thiazolidine-2,4-dione (5)

To a mixture of 2-((5-(1-(4-(trifluoromethyl)phenyl)-1H-imidazol-5-yl)quinolin-8-yl)oxy) acetaldehyde (5) (5g, 0.012 mol), thiazolidine-2,4-dione (1.62 g, 0.013 mol) in EtOH (50 mL) was added piperdine ( 2 mL) and heated at 90 °C for 6 h. The progress of reaction was monitored by TLC. After completion, Reaction mixture was evaporated under vacuum to gave crude residue. The residue was diisolve in water(100 mL) and filtered under vaccum and dried to gave (Z]-5-(2-((5-(1-(4- (trifluoromethyl) phenyl)-1H-imidazol-5-yl)quinolin-8-yl)oxy) ethylidene) thiazolidine-2,4-dione (6) ( 5.5 g, Yield: 88% ) as a solid ( brown colour).M.p:240-243 °C. IR (KBr, cm-1): 3050, 1725, 1650, 1503, 1050, 691, 644.1HNMR ( d6-DMSO, 400 mHz) : 4.6 (dd, 1H), 4.61(dd, 1H), 6.15 (dd, 1H), 7.12 (m, 2H), 7.3 (d, 2H), 7.6-7.65 (m, 4H), 7.9(d, 1H), 8.4(d, 1H), 8.6 (brs, 1H), 8.87 (d, 1H) (Figure 12).

Step 6 : 3-( Amino substituted methyl)-5-(2-((5-(1-(4- (trifluoromethyl)phenyl)-1H-imidazol-5-yl)qumolm- 8-yl)oxy)ethylidene)thiazolidine-2,4-dione &7(a-f)

To a mixture of (Z)-5-(2-((5-(1-(4-(trifluoromethyl) phenyl]- 1H-imidazol-5-yl)quinolin-8-yl)oxy)ethylidene) thiazolidine-2,4- dione (6) ( 500 mg, ), 2o Amine (1.1 eq), Para formal dehyde (3 eq) in EtOH (50 mL) was added Sc(OTf)3 (0.1 eq) and heated for 8 h. The progress of reaction was monitored by TLC. After completion, EtOH was evaporated under vaccum to give crude product. The crude was purified by reverse-phase column chromatography (C18 silica, Eluent: 30% ACN-MeOH-H2O,0.01% TFA) isolated (Z)-3-(Amino substituted methyl)-5-(2-((5- (1-(4-(trifluoromethyl]phenyl]-1H-imidazol-5-yl)quinolin-8-yl) oxy)ethylidene) thiazolidine-2,4-dione &7(a-f). 1H NMR spectra of 7(a-f) was given below Table 1 & Figure 13.

a) 3-((4-oxopiperidin-1-yl)methyl)-5-(2-((5-(1-(4- (trifluoromethyl)phenyl)-1H-imidazol-5-yl)quinolin-8-yl) oxy)ethylidene)thiazolidine-2,4-dione (7a): M.p. 280-283 °C. IR (KBr, cm-1): 3050, 3010, 1720, 1655, 1600, 1320,770,620,. 1HNMR ( d6-DMSO, 400 mHz) : 2.4 (t, 4H), 2.8 (t, 4H), 4.65 (s, 2H,), 4. 68(dd,2H), 4.7 (dd,1H), 5.1(d, 2H), 6.8 (dd, 1H), 7.1 (m, 1H), 7.3 (d, 2H), 7.6 (m, 4H), 8.0 (d, 1H), 8.43 (d, 1H), 8.81(d, 1H). 13CNMR ( d6-DMSO, 400 mHz) : 45, 53, 65, 108, 120, 122, 124, 124.5, 131, 135, 139, 145,150,164, 173, 190.

b) 3-((4-methylpiperazin-1-yl)methyl)-5-(2-((5-(1-(4- (trifluoromethyl)phenyl)-1H-imidazol-5-yl)quinolin-8-yl) oxy)ethylidene)thiazolidine-2,4-dione (7b): M.p. 290-292 °C. IR (KBr, cm-1): 3350, 3050, 1660,1610, 1320,750, 6251HNMR ( d6-DMSO, 400 mHz) : 2.3 (s, 3H), 2.4 (d, 4H), 2.45 (d, 4H), 4.63 (s, 2H,), 4.66 (dd, 1H),4.67 (dd,1H), 6.81 (dd, 1H), 7.1 (m, 2H), 7.32 (d, 2H), 7.6 (m, 4H), 8.03 (d, 1H), 8.44 (d, 1H), 8.81(d, 1H). C-NMR ( d6-DMSO, 400 mHz) : 47, 53, 58, 65, 107, 121, 122, 124, 124.5, 127, 130, 134, 138, 145,150,163, 174.

c) tert-butyl4-((2,4-dioxo-5-(2-((5-(1-(4- (trifluoromethyl)phenyl)-1H-imidazol-5-yl)quinolin-8-yl) oxy)ethylidene)thiazolidin-3-yl)methyl)piperazine-1- carboxylate (7c): M.p. 260-2262 °C. IR (KBr, cm-1): , 3014, 1713, 1650, 1620, 1505, 1310, 1050, 698, 655, HNMR ( d6-DMSO, 400 mHz) : 1.4 (s, 9H ), 2.5 (t, 4H), 3.1(t, 4H), 2.45 (d, 4H), 4.5 (s, 2H,),4.68 (dd, 1H),4.69 (dd,1H), 6.83 (dd, 1H), 7.1 (m, 2H), 7.32 (d, 2H), 7.62 (m, 4H),7.9 (d, 1H), 8.42 (d, 1H), 8.82(d, 1H). 13C-NMR ( d6-DMSO, 400 mHz) : 31, 44, 52, 65, 78, 107, 121, 124, 127, 130, 132, 139, 145,154,162, 174.

d) 3-((4-ethylpiperazin-1-yl)methyl)-5-(2-((5-(1-(4- (trifluoromethyl)phenyl)-1H-imidazol-5-yl)quinolin-8-yl) oxy)ethylidene)thiazolidine-2,4-dione (7d): M.p. 290-292 °C. IR (KBr, cm-1): 3350, 3020, 1680,1620, 1330,750, 6251HNMR ( d6-DMSO, 400 mHz) : 1.2 (t, 3H ), 2.5 (m, 10H), 4.5 (s, 2H,), 4.67(d, 1H), 4.68(d, 1H), 6.80 (dd, 1H), 7.1 (m, 2H), 7.3(d, 2H), 7.62 (m, 4H),7.8 (d, 1H), 8.42 (d, 1H), 8.82(d, 1H). C-NMR ( d6- DMSO, 400 mHz) : 14, 50, 53,58,65, 108, 122, 124, 125, 130, 132, 145,149,165, 174.

e) 3-(morpholinomethyl)-5-(2-((5-(1-(4- (trifluoromethyl)phenyl)-1H-imidazol-5-yl)quinolin-8-yl) oxy)ethylidene)thiazolidine-2,4-dione (7e): M.p. 280-282 °C. IR (KBr, cm-1): 3016, 1720, 1650, 1503, 1300, 1050, 695, 650.1HNMR ( d6-DMSO, 400 mHz) : 2.6 (t, 4H ), 3.7 (t, 4H), 4.5 (s, 2H,), 4.68 (dd, 1H), 4.69 (dd,1H), 6.80 (dd, 1H), 7.15 (m, 2H), 7.25(d, 2H), 7.62 (m, 4H),7.9(d, 1H), 8.38 (d, 1H), 8.89(d, 1H). C-NMR (d6-DMSO, 400 mHz) : 53,65, 66,107, 123, 124, 125, 130, 132, 139, 145,149,164, 178.

f) 3 - (thi o mo rpho lino methyl) - 5 -(2-((5-(1-(4- (trifluoromethyl)phenyl)-1H-imidazol-5-yl)quinolin-8-yl) oxy)ethylidene)thiazolidine-2,4-dione (7f): M.p. 272-275 °C. IR (KBr, cm-1): 3080, 1730, 1645, 1520, 1310, 1125, 670, 660, 1HNMR ( d6-DMSO, 400 mHz) : 2.6 (t, 4H ), 2.8(t, 4H), 4.51 (s, 2H,), 4.66 (dd, 1H),4.67 (dd, 1H), 6.81 (dd, 1H), 7.15 (m, 2H), 7.25(d, 2H), 7.62 (m, 4H),7.9(d, 1H), 8.37 (d, 1H), 8.86(d, 1H). C-NMR ( d6-DMSO, 400 mHz) : 27,58,63, 106, 122,123, 124, 125, 130, 131, 135,139,145,149,164, 174.

Step 7: General procedure for -3-(sulfonyl derivative)- 5-(2-((5-(1-(4-trifluoromethyl)phenyl)-1H-imidazol- 5-yl)quinolin-8-yl)oxy)ethylidene)thiazolidine-2,4- dione (8a-f)

5-(2-((5-(1-(4-(trifluoromethyl)phenyl)-1H-imidazol-5-yl) quinolin-8-yl)oxy)ethylidene) thiazolidine-2,4-dione (500 mg,1.8mmol) in Dry DMF(5 mL) was added NaH (3 eq) at 0 °C under N2 atm and stirred for 1h. To that sulfonyl chloride (1.1 eq) was added and stirred for 5h.The pogress of reaction was monitored by TLC. The reaction mixture was poured in aq sat NaHCO3 and stirred for 15 min. The aq layer was extracted with 10% MeOH-CHCl3 (3x 25 ml) and dried over anhydrous Na2SO4, filtered and evaporated under vaccum to gave crude product. The crude product was purified by Column chromatography (100-200 mesh silica) isolated 3-(sulfonyl derivative)-5-(2-((5- (1-(4-(trifluoromethyl) phenyl)-1H-imidazol-5-yl)quinolin-8-yl) oxy) ethylidene) thiazolidine-2,4-dione (8a-f) (Figure 14 and Table 2).

i. 3-(methylsulfonyl)-5-(2-((5-(1-(4- (trifluoromethyl)phenyl)-1H-imidazol-5-yl)quinolin-8-yl) oxy)ethylidene)thiazolidine-2,4-dione(8a): M.p.280-283°C. IR (KBr, cm-1): 3040, 3025, 1730, 1645,1600, 1320,1070,770,715620,.1HNMR ( d6-DMSO, 400 mHz) : 2.8 (s, 3H), 4.67 (dd, 1H),4.68 (dd,1H), 6.8 (dd, 1H), 7.1 (m, 2H), 7.3(d, 2H), 7.6 (m, 4H),7.8 (d, 1H), 8.4 (d, 1H), 8.81(d, 1H). CNMR ( d6-DMSO, 400 mHz) : 42, 64, 106, 121, 122, 124, 124.5, 126,130, 135, 138,139, 145, 148, 164, 173.

ii. 3-(ethylsulfonyl)-5-(2-((5-(1-(4-(trifluoromethyl) phenyl)-1H-imidazol-5-yl)quinolin-8-yl)oxy)ethylidene) thiazolidine-2,4-dione(8b): M.p.:88-290 °C. IR (KBr, cm-1): 3040, 3025, 1730, 1645,1603, 1325, 1075,772,715 620,.1HNMR ( d6-DMSO, 400 mHz) : 1.3 (t, 3H), 3.45 (q, 2H), 4.65 (dd, 1H),4.67 (dd,1H), 6.8 (dd, 1H), 7.13 (m, 2H), 7.32(d, 2H), 7.65 (m, 4H), 7.8 (d, 1H), 8.41 (d, 1H), 8.82(d, 1H). 13CNMR ( d6-DMSO, 400 mHz) : 10, 52, 63, 106, 121, 122, 124, 124.5, 126,130, 135, 138,139, 145, 148, 164, 173.

iii. 3-tosyl-5-(2-((5-(1-(4-(trifluoromethyl) phenyl)-1H-imidazol-5-yl)quinolin-8-yl)oxy) ethylidene) thiazolidine-2,4-dione(8c): M.p. 300-302 °C. IR (KBr, cm-1):3050, 3030, 1735, 1640,1603, 1325, 1075,770,715 620.1HNMR ( d6-DMSO, 400 mHz) : 2.3 (s, 3H), 4.68 (dd, 1H), 4.69 (dd, 1H), 6.8 (dd, 1H), 7.13 (m, 2H), 7.32(d, 2H),7.4 (d, 2H), 7.65 (m, 4H),7.7 (d, 2H), 7.8 (d, 1H), 8.42 (d, 1H), 8.85(d, 1H). 13CNMR ( d6-DMSO, 400 mHz) : 20, 64, 107, 121, 122, 123, 124, 124.5,126,128, 130,132, 133 135, 138,139, 145, 148, 155, 165, 175.

iv. 3-((4-chlorophenyl)sulfonyl)-5-(2-((5-(1-(4- (trifluoromethyl)phenyl)-1H-imidazol-5-yl)quinolin-8- yl)oxy)ethylidene)thiazolidine-2,4-dione (8d): M.p. 290292 °C. IR (KBr, cm-1): 3070, 3020, 1720, 1620,1530,1325, 1080,770,720, 655.1HNMR ( d6-DMSO, 400 mHz) : 4.68(dd, H), 4.69 (dd, 1H), 6.85 (dd, 1H), 7.15 (m, 2H), 7.28(d, 2H),7.4(d, 2H), 7.63(m, 6H),7.8(d, 2H), 7.95(d, 1H), 8.5 (d, 1H), 8.87(d, 1H). 13CNMR ( d6-DMSO, 400 mHz) : 64, 108, 121, 122, 123, 124,

124.5, 126,128, 130,132, 133 135, 139, 145, 149, 155, 162, 173.

v. 3- ((4-bromophenyl)sulfonyl)-5 - (2- ((5 - (1-(4- (trifluoromethyl)phenyl)-1H-imidazol-5-yl)quinolin-8- yl)oxy)ethylidene)thiazolidine-2,4-dione (8e): M.p. 298300 °C. IR (KBr, cm-1): 3080, 3025, 1720, 1623,1530,1325, 1085,770,725, 655.1HNMR ( d6-DMSO, 400 mHz) : 4.68(dd, 1H), 4.69 (dd,1H), 6.87 (dd, 1H), 7.18 (m, 2H), 7.28(d, 2H),7.6(m, 4H), 7.88(m, 5H), 8.4 (d, 1H), 8.8(d, 1H). 13CNMR (d6-DMSO, 400 mHz): 64.2, 107, 121, 122, 123, 124, 124.5, 126,128, 130,132, 134, 136, 139, 146, 149, 155, 163, 174.

vi. 3 - ((4-nitrophenyl)sulfonyl) - 5 - (2- ((5- (1- (4- (trifluoromethyl)phenyl)-1H-imidazol-5-yl)quinolin-8-yl) oxy)ethylidene)thiazolidine-2,4-dione(8f): M.p. 305-308 °C. IR (KBr, cm-1): 3070, 3028, 1720, 1623,1535, 1400, 1328, 1085,770,730, 655. 1HNMR ( d6-DMSO, 400 mHz) :4.68(dd, 1H),4.6 9(dd, 1H), 6.87 (dd, 1H), 7.18 (m, 2H), 7.28(d, 2H),7.6(m, 4H), 7.8(d, 1H), 8.12 (d, 2H), 8.4 (m, 3H), 8.85(d, 1H). 13CNMR ( d6-DMSO, 400 mHz) : 64.2, 107, 121, 122, 123, 124, 124.5,126,128, 130,132, 134, 136, 139, 142, 146, 149, 151155, 164,174.5.

Conclusion

In this research work we successfully synthesized and characterization, mannich bases of quinoline attached imidazoline thiozolidine 2,4-one derivatives . We are planning to these derivatives check for biological evolution. The biological evolution details will include next journal.

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