- Substrate conformations set the rate of enzymatic acrylation by lipases
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Acrylates represent a class of α,β-unsaturated compounds of high industrial importance. We investigated the influence of substrate conformations on the experimentally determined reaction rates of the enzyme-catalysed transacylation of methyl acrylate and derivatives by ab initio DFT B3LYP calculations and molecular dynamics simulations. The results supported a least-motion mechanism upon the sp2 to sp3 substrate transition to reach the transition state in the enzyme active site. This was in accordance with our hypothesis that acrylates form productive transition states from their low-energy s-sis/s-trans conformations. Apparent kcat values were measured for Candida antarctica lipase B (CALB), Humicola insolens cutlnase and Rhizomucor miehei lipase and were compared to results from computer simulations. More potent enzymes for acryltransfer, such as the CALB mutant V190A and acrylates with higher turnover numbers, showed elevated populations of productive transition states.
- Syren, Per-Olof,Hult, Karl
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- Manganese Pincer Complexes for the Base-Free, Acceptorless Dehydrogenative Coupling of Alcohols to Esters: Development, Scope, and Understanding
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Aliphatic PNP pincer-supported earth-abundant manganese(I) dicarbonyl complexes behave as effective catalysts for the acceptorless dehydrogenative coupling of a wide range of alcohols to esters under base-free conditions. The reaction proceeds under neat conditions, with modest catalyst loading and releasing only H2 as byproduct. Mechanistic aspects were addressed by synthesizing key species related to the catalytic cycle (characterized by X-ray structure determination, multinuclear (1H, 13C, 31P, 15N, 55Mn) NMR, infrared spectroscopy, inter alia), by studying elementary steps connected to the postulated mechanism, and by resorting to DFT calculations. As in the case of related ruthenium and iron PNP catalysts, the dehydrogenation results from cycling between the amido and amino-hydride forms of the PNP-Mn(CO)2 scaffold. For the dehydrogenation of alcohols into aldehydes, our results suggest that the highest energy barrier corresponds to the hydrogen release from the amino-hydride form, although its value is close to that of the outer-sphere dehydrogenation of the alcohol into aldehyde. This contrasts with the ruthenium and iron catalytic systems, where dehydrogenation of the substrate into aldehyde is less energy-demanding compared to hydrogen release from the cooperative metal-ligand framework.
- Nguyen, Duc Hanh,Trivelli, Xavier,Capet, Frédéric,Paul, Jean-Fran?ois,Dumeignil, Franck,Gauvin, Régis M.
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- Reaction of Primary Alkyl Hydroperoxides with Sulphamoyl Chloride: Alkyl(sulphamoyl)peroxides. Peroxo Compounds, XVIII
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The novel peroxides H2NSO2OOCH2R (1a: R=CH2CH3; 1b: R=CH2CH2CH3) are obtained by reaction of sulphamoyl chloride with the appropriate hydroperoxides in the presence of pyridine (temperature below -30 deg C, solvent diethyl ether).The solvent-free liquids 1 deflagrate at ca. 0 deg C.Hydrolysis or ammonolysis of 1 generates the hydroperoxide and sulphamic acid or sulphamide, respectively.Controlled thermolysis of 1 affords sulphamic acid and carbonyl compounds, i.e. propanal and n-propyl propanoate from 1a, butanal, 2-methylpropanal and n-butyl n-butyrate from 1b.These products suggest a nonradical cyclic decomposition path-way. - Keywords: Sulphamoyl chloride, reaction with n-alkyl hydroperoxides; n-Alkyl hydroperoxides, reaction with sulphamoyl chloride; Alkyl(sulphamoyl)peroxides, preparation and thermolysis
- Blaschette, Armand,Safari, Hassan
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- Predicting a Sharp Decline in Selectivity for Catalytic Esterification of Alcohols from van der Waals Interactions
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Controlling the selectivity of catalytic reactions is a critical aspect of improving energy efficiency in the chemical industry; thus, predictive models are of key importance. Herein the performance of a heterogeneous, nanoporous Au catalyst is predicted for the complex catalytic self-coupling of the series of C2–C4 alkyl alcohols, based solely on the known kinetics of the elementary steps of the catalytic cycle for methanol coupling, using scaling methods augmented by density functional theory. Notably, a sharp decrease in selectivity for ester formation with increasing molecular weight to favor the aldehyde due to van der Waals interactions of reaction intermediates with the surface was predicted and subsequently verified quantitatively by experiment. Further, the agreement between theory and experiment clearly demonstrates the efficacy of this approach for building a predictive model of catalytic behavior for a homologous set of reactants using a small set of experimental information.
- Friend, Cynthia M.,Luneau, Mathilde,Madix, Robert J.,Reece, Christian
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- The role of functionalized phosphines in the hydrogenation of carboxylic acids in the presence of phosphine substituted hydrido ruthenium complexes
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Hydrido ruthenium carbonyl complexes substituted by functionalized phosphines such as H4Ru4(CO)8[P(CH2OCOR) 3]4 have been synthesized and tested as catalysts in the hydrogenation of carboxylic acids. These complexes are more active than those reported previously, containing trialkyl- or triarylphosphines. On the basis of their behavior, their different activity has been explained in terms of an involvement of the phosphine ligand in the catalytic cycle. The ester group present in the phosphine P(CH2OCOR)3 is hydrogenated to produce an alcohol (RCH2OH) and a P(CH2OH) group which, in turn, reacts with the free acid present in solution to restore the P(CH2OCOR) group. This hypothesis has been confirmed by the reactivity of the possible intermediate H4Ru4(CO)8[P(CH2OH) 3]4 with acetic acid. Another support to this statement is the almost equal catalytic activity, displayed by H4Ru4(CO)8[P(CH2OCOR) 3]4 complexes, whatever the R group present, in the phosphine ligand, in the hydrogenation of carboxylic acids. These complexes, on the other hand, are less active than the corresponding tributylphosphine substituted ones in the hydrogenation of alkenes and ketones. Finally when the phosphine ligand is P(CH2CH2COOCH3)3 the ester group is not reduced and consequently the catalytic activity of this complex in the hydrogenation of carboxylic acids is very low.
- Salvini, Antonella,Frediani, Piero,Bianchi, Mario,Piacenti, Franco,Pistolesi, Leonardo,Rosi, Luca
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- CATALYTIC OXIDATION OF ALCOHOLS TO ESTERS WITH Ru3(CO)12
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Ru3(CO)12 is an efficient homogeneous catalyst precursor for the conversion 2RCH2OH-->RCO2CH2R.With aliphatic primary alcohols and benzylic alcohols yields and selectivities of ca. 90percent are obtained.The reaction requires a hydrogen acceptor molecule; triple bonds and activated double bonds, as well as ketones and aldehydes, function as H-acceptors.The reaction proceeds in two steps, with an aldehyde intermediate which subsequently oxidatively couples with an alcohol to generate an ester.In most cases the aldehyde is present in a steady state concentration implying the presence of an equilibrium system.A disproportionation alcohol aldehyde is a component of the above system.A catalytically active intermediate complex, Ru(CO)6(Ph2C2), was isolated when Ph2C2 was used as an acceptor.
- Blum, Yigal,Shvo, Youval
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- Transesterification via Baeyer-Villiger oxidation utilizing potassium peroxydisulfate (K2S2O8) in acidic media
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Baeyer-Villiger oxidation of ketones with potassium peroxydisulfate (K 2S2O8) and sulfuric acid generates the anticipated esters or lactones. These products are transformed into new esters (or hydroxy esters) in the presence of alcohols via transesterification under Baeyer-Villiger reaction conditions in one pot. Springer-Verlag 2010.
- Zarrabi,Mahmoodi,Marvi
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- Solvent-free oxidation of straight-chain aliphatic primary alcohols by polymer-grafted vanadium complexes
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Oxidovanadium(IV) complexes [VO(tertacac)2] (1), [VO(dipd)2] (2), and [VO(phbd)2] (3) were synthesized by reacting [VO(acac)2] with 2,2,6,6-tetramethyl-3,5-hepatanedione, 1,3-diphenyl-1,3-propanedione, and 1-phenyl-1,3-butanedione, respectively. Imidazole-modified Merrifield resin was used for the heterogenization of complexes 1–3. During the process of heterogenization, the V4+ center in complex 2 converts into V5+, whereas the other two complexes 1 and 3 remain in the oxidovanadium(IV) state in the polymer matrix. Theoretically, calculated IPA values of 1–3 suggest that 2 is prone to oxidation compared with 1 and 3, which was also supported by the absence of EPR lines in 5. Polymer-supported complexes Ps-Im-[VIVO(tertacac)2] (4), Ps-Im-[VVO2(dipd)2] (5), and Ps-Im-[VIVO(phbd)2] (6) were applied for the solvent-free heterogenous oxidation of a series of straight-chain aliphatic alcohols in the presence of H2O2 at 60°C and showed excellent substrate conversion specially for the alcohols with fewer carbon atoms. Higher reaction temperature improves the substrate conversion significantly for the alcohols containing more carbon atoms such as 1-pentanol, 1-hexanol, and 1-heptanol while using optimized reaction conditions. However, alcohols with fewer carbon atoms seem less affected by reaction temperatures higher than the optimized temperature. A decreasing trend in the selectivity(%) of carboxylic acid was observed with increasing carbon atoms among the examined alcohols, whereas the selectivity towards aldehydes increased. The order of efficiency of the supported catalysts is 4 > 6 > 5 in terms of turnover frequency (TOF) values and substrate conversion, further supported by theoretical calculations.
- Chaudhary, Nikita,Haldar, Chanchal,Kachhap, Payal
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- Hydrogenation of carboxylic acids catalyzed by half-sandwich complexes of iridium and rhodium
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A series of half-sandwich Ir and Rh compounds are demonstrated to be competent catalysts for the hydrogenation of carboxylic acids under relatively mild conditions. Of the structurally diverse group of catalysts tested for activity, a Cp*Ir complex supported by an electron-releasing 2,2′-bipyridine ligand was the most active. Higher activity was achieved with employment of Bronsted or Lewis acid promoters. Mechanistic studies suggest a possible reaction pathway involving activated carboxylic acid substrates. The hydrogenation reaction was shown to be general to a variety of aliphatic acids.
- Brewster, Timothy P.,Miller, Alexander J. M.,Heinekey, D. Michael,Goldberg, Karen I.
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- Highly efficient use of NaOCI in the Ru-catalysed oxidation of aliphatic ethers to esters
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The selectivity of α-oxidation of ethers to esters via RuNaOCI can be dramatically improved by pH control, at high substrate to catalyst ratios using a stoichiometric amount of hypochlorite in biphasic media at room temperature.
- Gonsalvi, Luca,Arends, Isabel W.C.E.,Sheldon, Roger A.
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- Anionic ruthenium iodocarbonyl complexes as selective dehydroxylation catalysts in aqueous solution
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The selective dehydroxylation in aqueous solution of C3-C5 polyols and C6 sugars in the presence of homogeneous ruthenium iodocarbonyl catalysts, - species, has been studied.Glycerol, pure or in dilute aqueous solution, is dehydroxylated to give n-propanol and its ethers with selectivities of up to 90percent.Xylitol and C6 sugars, glucose and fructose, are dehydrated and hydrogenated through initial formation of levulinic acid to give γ-valerolactone with high yields.The dehydroxylation of these polyhydroxylic substrates is made possible in water solution bythe bifunctional nature (acidity and hydrogenating ability) of the ruthenium catalystic system.The requirements necessary for the catalytic system to be active and stable in water have been studied, and the mechanism of the reaction discussed.
- Braca, Giuseppe,Galletti, Anna Maria Raspolli,Sbrana, Glauco
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- Laboratory studies of the OH-initiated photooxidation of di-n-propyl ether
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The OH-initiated photooxidation of di-n-propyl ether was investigated in this study. Di-n-propyl ether was mixed with nitric oxide and a hydroxyl radical precursor and irradiated using UV black lamps in a glass environmental chamber. Mass spectrometry was used as the primary analytical technique to monitor the reactants and products. FTIR spectroscopy was used to monitor formaldehyde. The products observed were propyl formate, acetaldehyde, propionaldehyde, and propyl propionate, with molar yields relative to di-n-propyl ether concentration loss of 0.61±0.044, 0.60±0.057, 0.15±0.062, and 0.043±0.015, respectively. Errors represent ±2σ. Nitrates could not be quantified because of a lack of commercially available standards. However, evidence exists for nitrate formation from the photooxidation of di-n-propyl ether. Formaldehyde concentrations were negligible. Mechanism predictions were performed on the di-n-propyl ether/OH system using the Carter kinetic software. Propyl formate and acetaldehyde yields were reasonably predicted (under 11.7% error). However, propionaldehyde and propyl propionate yields were vastly underpredicted, and examination of the experimental data suggested secondary production of both propionaldehyde and propyl propionate. Reactions were proposed for the photolysis and OH-initiated photooxidation of a primary nitrate product (1-propoxy propyl nitrate) that resulted in the formation of propionaldehyde and propyl propionate. Basic semiempirical computational chemistry calculations at the UHF/PM3 level of theory were performed using Hyperchem to investigate pathways for the secondary formation of propionaldehyde in particular.
- Sempeles, John,Andino, Jean M.
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- Selective Oxidation of Alkanes and Ethers mediated by Ruthenium(II) Complexes
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Selective hydroxylation (or ketonization) of cyclic alkanes and conversion of ethers to esters and of secondary alcohols to ketones, with significant rates (up to ca. 1 turnover per minute at room temperature), were achieved by using hypochlorite as oxidant and a choice of ruthenium(II) complexes as catalysts, in a biphastic water-dichloromethane system.
- Bressan, Mario,Morvillo, Antonino
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- Formation of Ketone Ions Upon the Loss of CH2O from Ionized Esters
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Unimolecular and collision-induced decomposition of the products of CH2O loss from propyl propanoate and butyl butanoate demonstrate that the respective products are the 3-pentanone and 4-heptanone ions.
- Lin, Thomas,Hudson, Charles E.,McAdoo, David J.
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- Synthesis and crystal structures of three amidinatoaluminum compounds and their catalytic behavior in the Tishchenko reaction
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Three amidinatoaluminum compounds, [{MeC(NCy)2}AlMe(μ-OMe)]2 (1), [{(PhN)MeC(NCy)}AlMe(μ-OMe)]2 (2) and [{(PhN)MeC(NtBu)}AlMe(μ-OMe)]2 (3), were prepared by the insertion reaction of oxygen with the corresponding aluminum amidinate in high yield and characterized by 1H and 13C NMR spectra and single crystal X-ray diffraction analysis. 1-3 were used as pre-catalysts to catalyze the Tishchenko reaction and both 2 and 3 exhibited good to excellent catalytic activity under mild conditions.
- Zhang, Shaofeng,Han, Hongfei,Guo, Zhiqiang,Tong, Hongbo,Wei, Xuehong
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- Oxidation of Alcohols and Ethers Using Sodium Bromate-Hydrobromic Acid System
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Reaction of primary alcohols or simple ethers, α,ω-diols or cyclic ethers, and secondary alcohols with sodium bromate in the presence of catalytic amount of hydrobromic acid under mild conditions gave dimeric esters, lactones, and ketones in fairly good yields, respectively.
- Kajigaeshi, Shoji,Nakagawa, Takashi,Nagasaki, Noritaka,Yamasaki, Hiromochi,Fujisaki, Shizuo
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- Homogeneous Catalytic Hydrogenation of Carbocyclic Acid Esters to Alcohols
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The homogeneous catalytic hydrogenation of activated and simple aliphatic carboxylic acid esters to their corresponding primary alcohols has been accomplished under mild conditions using a novel anionic ruthenium hydride complex.
- Grey, Roger A.,Pez, Guido P.,Wallo, Andrea,Corsi, Jeff
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- Gas-phase, catalytic hydrodeoxygenation of propanoic acid, over supported group VIII noble metals: Metal and support effects
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The catalytic, gas-phase hydrodeoxygenation (HDO) of propanoic acid (PAc) over supported group VIII noble metals (M = Pd, Pt, Rh, Ru, Ni) was studied at 1 atm and 200-400 C. The activity and selectivity as a function of the reaction temperature was investigated. The reaction activity based on the TOF follows the order: Pd > Ru > Pt > Rh > Ni. The reaction over Pd, Pt and Rh catalysts proceeds mainly via decarbonylation (DCN) and decarboxylation (DCX) pathways at each reaction temperature. For Ru and Ni catalysts, while decarbonylation and decarboxylation pathways were predominant at lower temperatures (e.g., 200-250 C), at higher temperatures (>300 C) the formation of diethyl ketone was observed. Additionally, the kinetics of Pd over different supports (carbon, SiO2 and TiO2) were examined. The activity based on the TOF decreases in the following order: Pd/SiO2 > Pd/TiO2 > Pd/C. The reaction orders in acid and H2 were found to be approximately 0.5 and zero, respectively, regardless of the support. The apparent activation energies studied in a temperature range of 200-240 C, were 16.7 ± 0.6, 19.3 ± 1.6 and 11.7 ± 0.7 kcal/mole for Pd/C, Pd/TiO2 and Pd/SiO2 catalysts, respectively. The selectivity for Pd/C and Pd/SiO2 indicated mainly decarbonylation/decarboxylation and hydrogenation reaction pathways. In contrast, Pd/TiO2 at low temperatures (200 C) could generate decarbonylation and esterification products.
- Lugo-José, Yuliana K.,Monnier, John R.,Williams, Christopher T.
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- Dual utility of a single diphosphine-ruthenium complex: A precursor for new complexes and, a pre-catalyst for transfer-hydrogenation and Oppenauer oxidation
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The diphosphine-ruthenium complex, [Ru(dppbz)(CO)2Cl2] (dppbz = 1,2-bis(diphenylphosphino)benzene), where the two carbonyls are mutually cis and the two chlorides are trans, has been found to serve as an efficient precursor for the synthesis of new complexes. In [Ru(dppbz)(CO)2Cl2] one of the two carbonyls undergoes facile displacement by neutral monodentate ligands (L) to afford complexes of the type [Ru(dppbz)(CO)(L)Cl2] (L = acetonitrile, 4-picoline and dimethyl sulfoxide). Both the carbonyls in [Ru(dppbz)(CO)2Cl2] are displaced on reaction with another equivalent of dppbz to afford [Ru(dppbz)2Cl2]. The two carbonyls and the two chlorides in [Ru(dppbz)(CO)2Cl2] could be displaced together by chelating mono-anionic bidentate ligands, viz. anions derived from 8-hydroxyquinoline (Hq) and 2-picolinic acid (Hpic) via loss of a proton, to afford the mixed-tris complexes [Ru(dppbz)(q)2] and [Ru(dppbz)(pic)2], respectively. The molecular structures of four selected complexes, viz. [Ru(dppbz)(CO)(dmso)Cl2], [Ru(dppbz)2Cl2], [Ru(dppbz)(q)2] and [Ru(dppbz)(pic)2], have been determined by X-ray crystallography. In dichloromethane solution, all the complexes show intense absorptions in the visible and ultraviolet regions. Cyclic voltammetry on the complexes shows redox responses within 0.71 to -1.24 V vs. SCE. [Ru(dppbz)(CO)2Cl2] has been found to serve as an excellent pre-catalyst for catalytic transfer-hydrogenation and Oppenauer oxidation.
- Mukherjee, Aparajita,Bhattacharya, Samaresh
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p. 15617 - 15631
(2021/05/19)
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- Disproportionation of aliphatic and aromatic aldehydes through Cannizzaro, Tishchenko, and Meerwein–Ponndorf–Verley reactions
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Disproportionation of aldehydes through Cannizzaro, Tishchenko, and Meerwein–Ponndorf–Verley reactions often requires the application of high temperatures, equimolar or excess quantities of strong bases, and is mostly limited to the aldehydes with no CH2 or CH3 adjacent to the carbonyl group. Herein, we developed an efficient, mild, and multifunctional catalytic system consisting AlCl3/Et3N in CH2Cl2, that can selectively convert a wide range of not only aliphatic, but also aromatic aldehydes to the corresponding alcohols, acids, and dimerized esters at room temperature, and in high yields, without formation of the side products that are generally observed. We have also shown that higher AlCl3 content favors the reaction towards Cannizzaro reaction, yet lower content favors Tishchenko reaction. Moreover, the presence of hydride donor alcohols in the reaction mixture completely directs the reaction towards the Meerwein–Ponndorf–Verley reaction. Graphic abstract: [Figure not available: see fulltext.].
- Sharifi, Sina,Sharifi, Hannah,Koza, Darrell,Aminkhani, Ali
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p. 803 - 808
(2021/07/20)
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- Metal complex catalysts and method for catalytically reducing carboxylic acids
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The invention relates to a metal complex catalyst, which contains at least one of metal complexes with a chemical formula comprising a structural unit represented by a formula I. According to the invention, the center metal of the metal complex catalyst is iridium, and the metal complex catalyst is composed of pentamethylcyclopentadienyl, a bitetrahydropyrimidine ligand and proper coordination anions; the metal complex catalyst has activity on a carboxylic acid reduction reaction, and a carboxylic acid compound is reduced into an alcohol compound in the presence of hydrogen; and the method ismild in reaction condition, can be carried out at room temperature, and is good in catalytic performance and high in reduction product yield.
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Paragraph 0085-0144; 0145; 0146; 0167; 0168; 0178-0179
(2020/06/20)
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- Method for preparing organic carboxylic ester through combined catalysis of aryl bidentate phosphine ligand
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The invention discloses a method for preparing organic carboxylic ester by combined catalysis of an aryl bidentate phosphine ligand. The method comprises the following steps: under the action of a palladium compound/aryl bidentate phosphine ligand/acidic additive combined catalyst, carrying out a hydrogen esterification reaction on terminal olefin, carbon monoxide and alcohol so as to generate theorganic carboxylic ester with one more carbon than olefin. According to the invention, by adoption of the palladium compound/aryl bidentate phosphine ligand/acidic additive combined catalyst, good catalytic activity and selectivity for the hydrogen esterification reaction of the olefin are achieved, and olefin carbonylation to synthesize organic carboxylic ester can be efficiently catalyzed. Thearyl bidentate phosphine ligand has a rigid skeleton structure of a rigid ligand and the flexibility of a flexible ligand, so the aryl bidentate phosphine ligand has proper flexibility due to the characteristic that the aryl bidentate phosphine ligand is soft and rigid, and a most favorable coordination mode and a stable active structure in space are favorably formed. In addition, the aryl bidentate phosphine ligand has the advantages of high stability, simple and convenient synthesis method and the like; and a novel industrial technology is provided for production of organic carboxylate compounds.
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Paragraph 0037
(2020/05/29)
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- Method for synthesizing propionate through ester-ester exchange path
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The invention provides a method for synthesizing propionate through an ester-ester exchange path and relates to a method for synthesizing the propionate. According to the method, reaction raw materials include, but are not limited to ethyl formate, propyl formate, butyl formate, ethyl acetate, propyl acetate, butyl acetate and the like; the method for synthesizing the propionate through an ester exchange one-step method is adopted. A catalyst comprises alkaline materials including ionic liquid, soluble strong base, solid base and the like respectively; the catalyst has the advantages of high catalysis efficiency and no pollution. By taking methyl propionate and ethyl acetate reaction as an example, KOH is used as the catalyst, the mol ratio of the raw materials is 1 to 1, the reaction temperature is 60 DEG C and the reaction time is 5 min; the conversion ratios of the methyl propionate and the ethyl acetate can reach 70 percent or more; products comprise ethyl propionate and the methylacetate. The whole reaction path has the characteristics of short synthetic route, simple technological flow and high yield and the catalyst is stable, does not become inactive and can be repeatedlyutilized.
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Paragraph 0030-0031
(2019/04/04)
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- Preparation method for electronic-grade n-propyl propionate
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The invention relates to a preparation method for electronic-grade n-propyl propionate. The method comprises the following steps: performing a reaction on propionic acid and n-propanol to form crude n-propyl propionate under the catalysis of [HNMP]PTSA, performing reduced-pressure rectification, performing ion exchange resin adsorption impurity removal, and performing sub-boiling distillation to obtain the electronic-grade n-propyl propionate with a content of >= 99.99% and a metal ion content of less than 1 ppb, wherein the electronic-grade n-propyl propionate can be used as an electrolyte solvent in the lithium battery industry. According to the method provided by the invention, the catalyst used in the method has a high catalytic esterification rate, and the method adopts conventional purification equipment, has high product purity, is convenient to operate, and can realize industrialized production.
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Paragraph 0028; 0034; 0036; 0037; 0041-0043; 0058-0060
(2019/10/02)
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- Method for preparing propionate by ester alcohol exchange
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The invention discloses a method for preparing propionate by ester alcohol exchange, and relates to a method for preparing propionate. According to the invention, the method for synthesizing propionate by ester alcohol exchange of methyl propionate and various alcohols (including monohydric alcohols such as ethanol, propanol, butanol, tert-butanol, isopropanol, cyclohexanol, allyl alcohol and thelike, dihydric alcohols such as 1,3-propylene glycol and the like, glycerol and the like) is adopted, and methyl propionate and the alcohols are used as raw materials to carry out a reaction under catalysis of alkaline ionic liquid, soluble strong alkali or solid alkali to prepare higher propionate and methanol. According to the method, the synthetic route is short, and the reaction product is taken out through azeotropic extraction of the methyl propionate and methanol, so that the reaction is more thorough, and the target product is directly obtained by one step. The product obtained by thereaction only contains propionate and methanol, the whole reaction process is concise and efficient and is free of pollution, no byproducts are generated, and great significance is achieved for large-scale and low-cost production of propionate.
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Paragraph 0038-0039
(2019/07/04)
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- SNS-Ligands for Ru-Catalyzed Homogeneous Hydrogenation and Dehydrogenation Reactions
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A detailed study of literature-known and novel S-containing pincer-type ligands for ruthenium-catalyzed homogeneous hydrogenation and dehydrogenation reactions was carried out. The scope and limitations of these catalysts were carefully investigated, and it was shown that simple bench-stable SNS-Ru complexes can be used to facilitate the hydrogenation of a variety of different substrates at a maximum H2 pressure of 20 bar under operationally simple, easy to scale up, glovebox-free conditions by using starting materials and reagents that do not require any special purification prior to use. It was also shown that such complexes can be used to catalyze the dehydrogenative coupling of alcohols and amines to get amides as well as for the dehydrogenative dimerization of alcohols to esters.
- Sch?rgenhumer, Johannes,Zimmermann, Axel,Waser, Mario
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supporting information
p. 862 - 870
(2018/06/18)
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- Hydrogenation of Ketones and Esters Catalyzed by Pd/C?SiO2
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Hydrogenation of unsaturated ketones and esters with molecular hydrogen on the 5%Pd/C?SiO2 heterogeneous catalyst has been studied. The reaction direction and yield are determined by the starting compounds structure. Hydrogenation of unsaturated ketones containing phenyl group at the double carbon–carbon atom is accompanied by the reduction of the ketone group into the alcohol one. Hydrogenation of unsaturated esters is accompanied by transesterification.
- Akchurin,Baibulatov,Dokichev
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p. 195 - 198
(2018/03/26)
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- Efficient Palladium-Catalyzed Alkoxycarbonylation of Bulk Industrial Olefins Using Ferrocenyl Phosphine Ligands
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The development of ligands plays a key role and provides important innovations in homogeneous catalysis. In this context, we report a novel class of ferrocenyl phosphines for the alkoxycarbonylation of industrially important alkenes. A basic feature of our ligands is the combination of sterically hindered and amphoteric moieties on the P atoms, which leads to improved activity and productivity for alkoxycarbonylation reactions compared to the current industrial state-of-the-art ligand 1,2-bis((di-tert-butylphosphino)methyl)benzene). Advantageously, palladium catalysts with these novel ligands also enable such transformations without additional acid under milder reaction conditions. The practicability of the optimized ligand was demonstrated by preparation on >10 g scale and its use in palladium-catalyzed carbonylations on kilogram scale.
- Dong, Kaiwu,Sang, Rui,Fang, Xianjie,Franke, Robert,Spannenberg, Anke,Neumann, Helfried,Jackstell, Ralf,Beller, Matthias
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supporting information
p. 5267 - 5271
(2017/04/27)
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- Oxidative esterification of primary alcohols with TEMPO/CaCl2/Oxone under hydrous conditions
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Symmetric esters are important compounds in the chemical industry, which creates demand for simple and efficient synthetic routes. Oxidative esterification is a promising method to achieve these aims. Here, we show that TEMPO/CaCl2/Oxone forms a convenient catalytic system for the synthesis of the aforementioned symmetric esters from primary alcohols in a biphasic dichloromethane-water solvent mixture. The substrate scope of the reaction method is complementary to those previously published and the terminal oxidant appears to play an important role. In addition, the method is shown to oxidize thiols preferentially over alcohol functional groups to give disulfide-bridged compounds.
- Hackbusch, Sven,Franz, Andreas H.
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p. 2873 - 2876
(2016/06/14)
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- Dicopper Complexes with Anthyridine-Based Ligands: Coordination and Catalytic Activity
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Two new anthyridine-based ligands, 5-phenyl-2,8-bis(2-pyridinyl)-1,9,10-anthyridine (L3) and 5-phenyl-2,8-bis(6′-bipyridinyl)-1,9,10-anthyridine (L4), were designed for accommodation of dimetallic systems with the metal ions separated by 5 ?. Complexation of Cu(ClO4)2 with L3 and L4 provided the corresponding dicopper complexes [{Cu2(L3)(H2O)4(CH3CN)2}(ClO4)4] (3) and [{Cu2(L4)(μ-ClO4)2}(PF6)2] (4), respectively. Both complexes were characterized by spectroscopic methods, and the detail structural features were further confirmed by X-ray crystallography. Structural analyses of 3 and 4 reveal the Cu···Cu distances in the complexes being 4.9612(7) and 5.013 (2) ?, respectively. Both complexes are active in the catalytic oxidation of benzyl alcohols into the corresponding aldehydes. Furthermore, complex 4 appears to be a good catalyst for the oxidative coupling of primary alcohols into the corresponding esters with the use of hydrogen peroxide as the oxidant in an aqueous medium. The possible cooperative interactions between the metal ions during the catalysis are discussed.
- Huang, Da-Wei,Liu, Yi-Hung,Peng, Shie-Ming,Liu, Shiuh-Tzung
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p. 151 - 158
(2016/02/05)
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- A catalytic ketone compound is oxidized the method for preparing the lactone
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The invention discloses a method for preparing lactone through catalyzing the oxidation of a ketone compound. The method which treats the ketone compound as a raw material and carbon nanotubes as a catalyst comprises a step of adding an organic solvent and an assistant, and a step of carrying out a catalysis reaction at 25-120DEG C under normal pressure to obtain a lactone compound in a high selectivity manner. The method has the advantages of simple process, mild condition, high selectivity, safety, easy catalyst recovery and the like.
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Paragraph 0021; 0022
(2017/02/24)
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- Biocatalytic Characterization of Human FMO5: Unearthing Baeyer-Villiger Reactions in Humans
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Flavin-containing mono-oxygenases are known as potent drug-metabolizing enzymes, providing complementary functions to the well-investigated cytochrome P450 mono-oxygenases. While human FMO isoforms are typically involved in the oxidation of soft nucleophiles, the biocatalytic activity of human FMO5 (along its physiological role) has long remained unexplored. In this study, we demonstrate the atypical in vitro activity of human FMO5 as a Baeyer-Villiger mono-oxygenase on a broad range of substrates, revealing the first example to date of a human protein catalyzing such reactions. The isolated and purified protein was active on diverse carbonyl compounds, whereas soft nucleophiles were mostly non- or poorly reactive. The absence of the typical characteristic sequence motifs sets human FMO5 apart from all characterized Baeyer-Villiger mono-oxygenases so far. These findings open new perspectives in human oxidative metabolism.
- Fiorentini, Filippo,Geier, Martina,Binda, Claudia,Winkler, Margit,Faber, Kurt,Hall, Mélanie,Mattevi, Andrea
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p. 1039 - 1048
(2016/05/19)
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- Process for the preparation of propionic acid methyl ester
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The invention relates to a preparation method of propionate, belonging to the technical field of preparation of organic substances. Propanoic acid and monobasic alcohol are subjected to esterification reaction under the action of a gel-type strong-acid ion exchange resin catalyst to generate the propionate. The gel-type strong-acid ion exchange resin is a hydrogen-type styrene-stilbene copolymer with sulfonate group, and the pore size of the resin is less than 8nm. The preparation method provided by the invention uses the catalyst to effectively adsorb the reaction impurities and enhance the product purity; and the catalyst has the advantages of favorable catalytic effect and low corrosivity, and can be easily separated from the product.
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Paragraph 0049; 0050; 0051; 0052; 0053; 0054
(2016/12/22)
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- DEHYDROGENATION CATALYST, AND CARBONYL COMPOUND AND HYDROGEN PRODUCTION METHOD USING SAID CATALYST
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Objects of the present invention are to provide a novel dehydrogenation reaction catalyst, to provide a method that can produce a ketone, an aldehyde, and a carboxylic acid with high efficiency from an alcohol, and to provide a method for efficiently producing hydrogen from an alcohol, formic acid, or a formate, and they are accomplished by a catalyst containing an organometallic compound of Formula (1).
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Paragraph 0176
(2016/10/31)
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- Nitrous Oxide as a Hydrogen Acceptor for the Dehydrogenative Coupling of Alcohols
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The oxidation of alcohols with N2O as the hydrogen acceptor was achieved with low catalyst loadings of a rhodium complex that features a cooperative bis(olefin)amido ligand under mild conditions. Two different methods enable the formation of either the corresponding carboxylic acid or the ester. N2 and water are the only by-products. Mechanistic studies supported by DFT calculations suggest that the oxygen atom of N2O is transferred to the metal center by insertion into the Rh-H bond of a rhodium amino hydride species, generating a rhodium hydroxy complex as a key intermediate.
- Gianetti, Thomas L.,Annen, Samuel P.,Santiso-Quinones, Gustavo,Reiher, Markus,Driess, Matthias,Grützmacher, Hansj?rg
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supporting information
p. 1854 - 1858
(2016/02/03)
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- Conversion of a metal-organic framework to N-doped porous carbon incorporating Co and CoO nanoparticles: Direct oxidation of alcohols to esters
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A Co-based metal-organic framework, ZIF-67, has been exploited as a selflate to afford N-doped porous carbon incorporating Co NPs with surface-oxidized CoO species, which exhibit excellent catalytic activity, selectivity and magnetic recyclability toward the direct oxidation of alcohols to esters with O2 as a benign oxidant under mild conditions.
- Zhou, Yu-Xiao,Chen, Yu-Zhen,Cao, Lina,Lu, Junling,Jiang, Hai-Long
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supporting information
p. 8292 - 8295
(2015/05/13)
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- Continuous flow Fischer esterifications harnessing vibrational-coupled thin film fluidics
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Rapid Fischer esterification reactions occur under solventless, continuous flow conditions in dynamic thin films. This methodology uses limited catalyst, require no additional heat input and occurs within the confinements of an inexpensive vortex fluidic device (VFD). The associated mechanoenergy is primarily delivered from two types of vibration, which are manifested in sharp increases in the yield of the reactions. These vibrations promote the existence of Faraday waves that alter the instantaneous shear rates of the reactants within the rotating tube. Tuning the rotational speed of the device allows harmonic vibrations to be utilized in the synthesis of alkyl-based esters within both a high and low contact angle NMR tube. This journal is
- Britton, Joshua,Dalziel, Stuart B.,Raston, Colin L.
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p. 1655 - 1660
(2015/02/02)
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- CATALYST FOR DEHYDROGENATION, AND MANUFACTURING METHOD OF CARBONYL COMPOUND AND HYDROGEN USING THE CATALYST
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PROBLEM TO BE SOLVED: To provide a novel catalyst for dehydrogenation, a method for manufacturing ketone, aldehyde and carboxylic acid from alcohols by using the catalyst at high efficiency, and a method for efficiently manufacturing hydrogen from formic acid and formate. SOLUTION: There is provided a catalyst containing the formula (1), where Ar is benzene which may have a substituent or a cyclopentadienyl group which may have a substituent and M represents ruthenium, rhodium or iridium, e.g. an organic metal compound represented by Compounds 1 and 2. COPYRIGHT: (C)2015,JPO&INPIT
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Paragraph 0133; 0134
(2017/01/02)
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- Carboxyl activation of 2-mercapto-4,6-dimethylpyrimidine through n-acyl-4,6-dimethylpyrimidine-2-thione: A chemical and spectrophotometric investigation
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2-Mercapto-4,6-dimethylpyrimidine, as effective carboxyl activating group, has been successfully proved by converting it into respective acyl derivatives and the subsequent conversion to the amides and esters respectively using amines, amino alcohols and alcohols. The aminolysis and esterification were monitored chemically and spectrophotometrically. This paved way to establish that the above mercaptopyrimidine derivative is an efficient carboxyl activating group applicable in solid phase peptide synthesis.
- Rajan
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p. 287 - 291
(2015/01/30)
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- A method for esterification reaction rate prediction of aliphatic monocarboxylic acids with primary alcohols in 1,4-dioxane based on two parametrical taft equation
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Esterification reaction rates of aliphatic monocarboxylic acids with primary alcohols in 1,4-dioxane as inert solvent were investigated. Acids were esterified with 1-propanol and alcohols with acetic acid as model reactants at a constant temperature of 60°C, at a fixed ionic strength and pH in a batch reactor with a constant volume. For evaluation of reaction rates, an exact kinetic equation for the equilibrium reaction was applied. Under these conditions and for low reactants, concentrations reaction rate depends only on the structure of reactants and, therefore, can be predicted by a correlation equation with two Taft coefficients (inductive and steric effects). From these equations, it is possible to estimate the esterification reaction rate constant for other acid-alcohol pairs. This methodology may also be suitable for other kinetic systems measured under comparable experimental conditions.
- Vojtko, Jan,Tomcik, Peter
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p. 189 - 196
(2014/02/14)
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- METHODS OF CONVERTING POLYOLS
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Methods for converting polyols are provided. The methods provided can include using a metal pincer catalyst (e.g., an iridium pincer catalyst) to remove at least one alcohol group from a polyol. The methods provided can include converting glycerol to 1,3-propanediol.
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Paragraph 0094-0095
(2015/01/06)
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- Electroorganic synthesis of esters and ketones at the platinum anode in aqueous medium
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Elcctroorganic synthesis of esters from the saturated primary aliphatic alcohols and ketones from the secondary aliphatic alcohols have been carried out in electrooxidation at the platinum anode in aqueous medium. This is an important reaction because of high oxidation potential of alcohols. Electrochemical oxidation has been carried out under controlled potential electrolysis at room temperature in a three electrode cell assembly containing two platinum electrodes In the form of square plates as working as well as counter electrode and saturated calomel electrode was used as a reference electrode. The structures of compounds were confirmed from the IR, NMR, inass spectral and microanalyses. The products formed during the electrooxidation of ethanol, propanol, 1-butanol, 1-pentanol, 2-butanol and sec-butyl alcohol are reported here.
- Kumar, Sanjeev
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p. 739 - 744
(2013/08/23)
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- Selective oxidation of alcohols to esters using heterogeneous Co 3O4-N@C catalysts under mild conditions
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Novel cobalt-based heterogeneous catalysts have been developed for the direct oxidative esterification of alcohols using molecular oxygen as benign oxidant. Pyrolysis of nitrogen-ligated cobalt(II) acetate supported on commercial carbon transforms typical homogeneous complexes to highly active and selective heterogeneous Co3O4-N@C materials. By applying these catalysts in the presence of oxygen, the cross and self-esterification of alcohols to esters proceeds in good to excellent yields.
- Jagadeesh, Rajenahally V.,Junge, Henrik,Pohl, Marga-Martina,Radnik, Joerg,Brueckner, Angelika,Beller, Matthias
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supporting information
p. 10776 - 10782
(2013/08/23)
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- A strategy for separating and recycling solid catalysts based on the pH-triggered pickering-emulsion inversion
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Turn you inside out: A novel method for performing in situ separation and recycling of submicrometer-sized solid catalysts is developed based on the pH-triggered inversion of Pickering emulsions (see scheme; o=oil, w=water). Solid catalysts can be recycled 36 times without significant loss of activity. The method differs from conventional methods in terms of speed, energy consumption, catalyst separation, and recycling effectiveness. Copyright
- Yang, Hengquan,Zhou, Ting,Zhang, Wenjuan
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supporting information
p. 7455 - 7459
(2013/07/26)
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- SYNTHESIS OF HIGH CALORIC FUELS AND CHEMICALS
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In one embodiment, the present application discloses methods to selectively synthesize higher alcohols and hydrocarbons useful as fuels and industrial chemicals from syngas and biomass. Ketene and ketonization chemistry along with hydrogenation reactions are used to synthesize fuels and chemicals. In another embodiment, ketene used to form fuels and chemicals may be manufactured from acetic acid which in turn can be synthesized from synthesis gas which is produced from coal, biomass, natural gas, etc.
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Paragraph 00109
(2013/05/23)
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- From esters to alcohols and back with ruthenium and osmium catalysts
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There and back again: Hydrogenation of esters and the reverse reaction of dehydrogenative coupling of alcohols are efficiently catalyzed by dimeric complexes of Ru and Os under neutral conditions. The Os dimer (see picture) is an outstanding catalyst for the hydrogenation of alkenoates and triglycerides, and allows production of fatty alcohols from olive oil. This complex converts ethanol into ethyl acetate and hydrogen under reflux. Copyright
- Spasyuk, Denis,Smith, Samantha,Gusev, Dmitry G.
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supporting information; experimental part
p. 2772 - 2775
(2012/05/20)
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- Determination of steric effect on the esterification of different alcohols with propanoic acid over cation-exchange resin catalyst Dowex 50Wx4
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This paper describes the application of LFER in the form of Taft correlation to understand the mechanism of the esterification of propanoic acid with different alcohols over heterogeneous catalyst, Dowex 50Wx4. The rate constant (k1) in the rate equation decreases with change of alcohols in the order methanol, ethanol, n-propyl, n-butyl, n-pentyl, iso-butyl, iso-propyl and sec-butyl (2-buthanol). The reaction of propanoic acid with alcohols fits the Taft equation, log k1.kCH3 = 1.0061 Es K 0.0012, which implies that the steric effect of the substituent governs that reaction and the mechanism is similar between the different alcohols. The experimental results were modelled according to a simple second-order model. It was found that the equilibrium constant of this reaction does not depend on the structure of the organic alcohols, and has for 333 K the value 4.04. by Oldenbourg Wissenschaftsverlag, Munchen.
- Erdem, Beyhan,Cebe, Mustafa
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experimental part
p. 125 - 136
(2011/04/24)
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- Rhodium(III)-catalyzed dimerization of aldehydes to esters
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No sooner said than done: A rhodi- um(III) hydride complex is an outstandingly effective and selective catalyst for the dimerization of aldehydes to the corresponding esters (see scheme). Evidence for an unusual mechanism in catalysis by rhodium is given.
- Tejel, Cristina,Ciriano, Miguel A.,Passarelli, Vincenzo
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experimental part
p. 91 - 95
(2011/03/21)
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- CONVERSION OF OXYGENATES TO HYDROCARBON FUELS BY DEOXYGENATION
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Oxygenates from biomass, particularly hydroxyl-substituted C2-plus hydrocarbons, are treated for removal of some or all of their oxygen atoms and for chain lengthening by carbon-carbon coupling in a single reaction medium in the gas phase over a solid catalyst.
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Page/Page column 32-33
(2011/10/10)
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- Increased activity of enzymatic transacylation of acrylates through rational design of lipases
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A rational design approach was used to create the mutant Candida antarctica lipase B (CALB, also known as Pseudozyma antarctica lipase B) V190A having a kcat three times higher compared to that of the wild type (wt) enzyme for the transacylation of the industrially important compound methyl methacrylate. The enzymatic contribution to the transacylation of various acrylates and corresponding saturated esters was evaluated by comparing the reaction catalysed by CALB wt with the acid (H2SO4) catalysed reaction. The performances of CALB wt and mutants were compared to two other hydrolases, Humicola insolens cutinase and Rhizomucor mihei lipase. The low reaction rates of enzyme catalysed transacylation of acrylates were found to be caused mainly by electronic effects due to the double bond present in this class of molecules. The reduction in rate of enzyme catalysed transacylation of acrylates compared to that of the saturated ester methyl propionate was however less than what could be predicted from the energetic cost of breaking the π-system of acrylates solely. The nature and concentration of the acyl acceptor was found to have a profound effect on the reaction rate.
- Syren, Per-Olof,Lindgren, Ebba,Hoeffken, Hans Wolfgang,Branneby, Cecilia,Maurer, Steffen,Hauer, Bernhard,Hult, Karl
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experimental part
p. 3 - 10
(2011/02/22)
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- Gold supported on nanocrystalline β-Ga2O3 as a versatile bifunctional catalyst for facile oxidative transformation of alcohols, aldehydes, and acetals into esters
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Facile oxidative transformation of alcohols, aldehydes, and acetal into esters has been demonstrated using bifunctional catalyst of gold supported nanocrystalline β-Ga2O3. The study used alcoholic gel-precipitation method to prepare nanocrystalline support and X-ray diffraction (XRD) to characterize the diffraction features of synthesized nanocrystalline support. The study observed that the Au/β-Ga 2O3 catalyst can be reused after aerobic oxidation with maintaining catalytic activity and selectivity for oxidative esterification. The study also observed that aromatic and aliphatic primary alcohols can be converted into their methyl, ethyl, or propyl esters with high selectivities. The study also found that the esters produced after esterification were in good yields.
- Su, Fang-Zheng,Ni, Ji,Sun, Hao,Cao, Yong,He, Yong,Fan, Kang-Nian
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supporting information; experimental part
p. 7131 - 7135
(2009/08/07)
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- PRODUCTION OF ESTERS
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This invention relates to a process for the hydroesterification of olefins in which a hydrocarbon stream containing olefins is reacted with CO and an alcohol in the presence of a catalyst to form a hydrocarbon stream containing esters, wherein the alcohol has more than one carbon atom. The hydroesterification reaction is typically carried out in the presence of a catalyst comprising cobalt and a nitrogen-containing additive such as pyridine and the olefins may be branched. The invention also relates to a process for preparing an alkoxylated ester suitable for use as a surfactant molecule in detergent formulations.
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Page/Page column 22; sheet 9/11
(2008/06/13)
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- Promoting gold nanocatalysts in solvent-free selective aerobic oxidation of alcohols
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A trace amount of metal carbonate, acetate or borate significantly boosts gold nanocatalysts in selective aerobic oxidation of alcohols under mild solvent-free conditions. The Royal Society of Chemistry.
- Zheng, Nanfeng,Stucky, Galen D.
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p. 3862 - 3864
(2008/03/14)
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- ZrOCl2·8H2O: An efficient, cheap and reusable catalyst for the esterification of acrylic acid and other carboxylic acids with equimolar amounts of alcohols
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Esterifications of carboxylic acids with equimolar amount of alcohols could be efficiently catalyzed by ZrOCl2·8H2O. Acrylate esters were obtained in good yields under solvent-free conditions at ambient temperature. The esterification of other carboxylic acids with alcohols also proceeded at ambient temperature or at 50°C to afford esters in high yields. If the esterification was performed in toluene under azeotropic reflux conditions to remove water, both the catalytic activity of ZrOCl 2·8H2O and the rate of esterification could be increased greatly. Furthermore, in the present catalytic system, the esters could be easily separated from the reaction mixtures and the catalyst could be easily recovered and reused.
- Sun, Hong-Bin,Hua, Ruimao,Yin, Yingwu
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p. 263 - 271
(2007/10/03)
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- Compositions related to a novel endophytic fungi and methods of use
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This invention provides pesticidally effective compositions related to a novel endophytic fungi named Muscodor. Specifically, the invention relates to commercially useful formulations of Muscodor and methods for preparing such formulations. It also provides various synthetic pesticidal mixtures of volatile organic compounds isolatable from Muscodor grown on various substrates. Also provided are methods for inhibiting the growth of organisms, such as microbes, insects, and nematodes by exposing such organisms or the habitats thereof to the above Muscodor-related compositions.
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- Novel endophytic fungi and methods of use
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This invention provides a novel endophytic fungus, Muscodor, that produces a mixture of volatile antibiotics with activity on specific plant pathogens, bacteria, nematodes and insects. Also provided is a method for treating or protecting plants, soil and seeds from microbial infections comprising applying an effective amount of a volatile antibiotic producing Muscodor sp. The invention also relates to fungicidal, bactericidal, insecticidal and nematicidal compositions comprising this novel Muscodor strain and the antibiotics and metabolites produced by this strain either alone, or in combination with other chemical and biological pesticides. Also provided is a method for identifying and isolating related gas producing fungi.
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- HOMOGENOUS PROCESS FOR THE HYDROGENATION OF CARBOXYLIC ACIDS AND DERIVATIVES THEREOF
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A homogenous process for the hydrogenation of the carboxylic acids and/or derivatives thereof in the presence of a catalyst comprising ruthenium, rhodium, iron, osmium or palladium, and an organic phosphine is described in which the hydrogenation is carried out in the presence of at least about 1% by weight water. A process for regenerating a catalyst comprising ruthenium, rhodium, iron, osmium or palladium and an organic phosphine is also described in which the regeneration is carried out in the presence of hydrogen and water.
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Page/Page column 11-12
(2008/06/13)
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- The Effect of pH Control on the Selective Ruthenium-Catalyzed Oxidation of Ethers and Alcohols with Sodium Hypochlorite
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Highly selective oxidations of ethers to esters or lactones and of secondary alcohols to ketones were achieved using catalytic amounts of various Ru precursors and the theoretical amount of NaOCl. Reactions were carried out in biphasic solvent mixtures at constant pH 9-9.5 via either feed-on-demand addition of HCl and NaOH or in the presence of NaHCO3/Na 2CO3 buffer. The catalyst could be easily recycled for at least 4 times with only minor loss in selectivity. Products were generally recovered by simple phase separation and evaporation of the organic solvent. The effects of catalyst precursor, additives and pH control method are also described.
- Gonsalvi, Luca,Arends, Isabel W. C. E.,Moilanen, Pasi,Sheldon, Roger A.
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p. 1321 - 1328
(2007/10/03)
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- Generation of alkyl hypochlorites in oxidation of alcohols with carbon tetrachloride catalyzed by vanadium and manganese compounds
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Primary alcohols and diols with various structures were subjected to transformations into esters, aldehydes, ketones, and lactones under the action of carbon tetrachloride in the presence of manganese compounds (MnCl 2, MnO2, Mn(OAc)2, Mn(acac)3) and vanadium compounds (VCl5, V2O5, VO(acac) 2) as catalysts. These transformation proceeded with the involvement of alkyl hypochlorites, which were generated in the course of oxidation of alcohols with carbon tetrachloride catalyzed by manganese or vanadium compounds. The optimum molar ratios between the catalyst and reagents were determined, and the reaction conditions for the highly selective synthesis of esters, aldehydes, ketones, and lactones from alcohols were found.
- Khusnutdinov,Shchadneva,Baiguzina,Lavrentieva,Dzhemilev
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p. 2074 - 2079
(2007/10/03)
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