2306-88-9Relevant academic research and scientific papers
Oxoammonium salts. 9. Oxidative dimerization of polyfunctional primary alcohols to esters. An interesting β oxygen effect
Merbouh, Nabyl,Bobbitt, James M.,Brueckner, Christian
, p. 5116 - 5119 (2004)
The use of the oxidant 4-acetylamino-2,2,6,6-tetramethylpiperidine-1- oxoammonium tetrafluoroborate in combination with pyridine for the oxidative, dimeric esterification of primary alcohols is described. The ester is the predominant product of the reaction with alcohols containing a β oxygen. In the absence of a β oxygen, the corresponding aldehyde is found in appreciable amounts, but a concentration effect can be observed. In the absence of pyridine, little ester is formed, and no appreciable reaction takes place with β-oxygenated compounds. δ Lactones have been prepared from diethylene glycol and 2,2′-thiodiethanol, without sulfur oxidation.
Microwave effect on fischer esterification
Koshima, Hideko,Miyazaki, Kiminori,Ishii, Saori,Asahi, Toru
, p. 505 - 507 (2016)
Upon microwave irradiation, esterification of octanoic acid with 1-octanol in the presence of hydrochloric acid as an acid catalyst proceeded more efficiently in glass vessels than in silicon carbide (SiC) vessels, affording 1-octyl octanoate in higher yields and revealing microwave effects during esterification.
Green Oxidation of n-Octanol on Supported Nanogold Catalysts: Formation of Gold Active Sites under Combined Effect of Gold Content, Additive Nature and Redox Pretreatment
Pakrieva,Kolobova,Mamontov,Bogdanchikova,Farias,Pascual,Cortés Corberán,Martinez Gonzalez,Carabineiro,Pestryakov
, p. 1615 - 1624 (2019)
The combined influence of gold content (0.5 or 4 wt. %), modifying additives (La or Ce oxides) and redox pretreatments (H2 or O2) on catalytic properties and formation of active sites of Au/TiO2 in the selective oxidation of n-octanol under mild conditions was studied. Samples were characterized by BET, XRD, EDX, ICP, TEM, STEM-HAADF, CO2-TPD, H2-TPR and XPS methods. The order of catalytic activity depended on the support nature for all treated samples, as follows: Au/La2O3/TiO2>Au/CeO2/TiO2>Au/TiO2. The catalytic activity enhanced with the increase of gold loading in the samples with hydrogen pretreatment, while after the oxidative pretreatment of the catalysts the opposite dependence of the activity with the gold content was found. This catalytic behavior was explained by a change in the surface concentration of monovalent gold ions, which seemed to be the active sites. The most active catalyst, 0.5 % Au/La2O3/TiO2, pretreated in oxidative atmosphere, had the highest surface concentration of monovalent gold ions.
Synthesis of Large Mesoporous-Macroporous and High Pore Volume, Mixed Crystallographic Phase Manganese Oxide, Mn2O3/Mn3O4 Sponge
Meguerdichian, Andrew G.,Shirazi-Amin, Alireza,Moharreri, Ehsan,Achola, Laura A.,Murphy, Steven C.,Macharia, John,Zhong, Wei,Jafari, Tahereh,Suib, Steven L.
, p. 6946 - 6956 (2018)
The controlled synthesis of mixed crystallographic phase Mn2O3/Mn3O4 sponge material by varying heating rates and isothermal segments provides valuable information about the morphological and physical properties of the obtained sample. The well-characterized Mn2O3/Mn3O4 sponge and applicability of difference in reactivity of H2 and CO2 desorbed during the synthesis provide new developments in the synthesis of metal oxide materials with unique morphological and surface properties. We report the preparation of a Mn2O3/Mn3O4 sponge using a metal nitrate salt, water, and Dextran, a biopolymer consisting of glucose monomers. The Mn2O3/Mn3O4 sponge prepared at 1 °C·min-1 heating rate to 500 °C and held isothermally for 1 h consisted of large mesopores-macropores (25.5 nm, pore diameter) and a pore volume of 0.413 mL/g. Furthermore, the prepared Mn2O3/Mn3O4 and 5 mol %-Fe-Mn2O3/Mn3O4 sponges provide potential avenues in the development of solid-state catalyst materials for alcohol and amine oxidation reactions.
Cloning, overexpression, and characterization of a novel organic solvent-tolerant lipase from Paenibacillus pasadenensis CS0611
Gao, Jiaxin,Ou, Xiaoyang,Xu, Pei,Zong, Minhua,Lou, Wenyong
, p. 937 - 945 (2018)
We found a novel lipase gene in the Paenibacillus pasadenensis CS0611 strain. The lipase gene sequence was cloned into the pET-28a expression vector to construct a recombinant lipase protein containing 6 × His tags at the C- and N-termini, respectively. High-level expression of the lipase in E.coli BL21 (DE3) was obtained upon induction with IPTG at 20 °C. The recombinant lipase activity was approximately 1631-fold higher than the wild type. His-tagged recombinant lipase was purified rapidly and efficiently by using Ni-charged affinity chromatography with 63.5% recovery and a purification factor of 10.78. The purified lipase was stable in a broad range of temperatures and pH values, with the optimal temperature and pH being 50 °C and 7.0, respectively. Its activity was stimulated to different degrees in the presence of metal ions such as Ca2+, Mg2+, and some non-ionic surfactants. In addition, the purified lipase was activated by a series of water-miscible organic solvents such as some short carbon chain alcohols and was highly tolerant to some water-immiscible organic solvents.
Highly selective and stable ZnO-supported bimetallic RuSn catalyst for the hydrogenation of octanoic acid to octanol
Hidajat, Marcel Jonathan,Hwang, Dong-Won,Yun, Gwang-Nam
, (2021/08/03)
The chemoselective hydrogenation of biomass-derived carboxylic acids is promising for the development of biorefineries. Herein, the selective conversion of octanoic acid to octanol over bimetallic RuSn/ZnO in a fixed-bed continuous reactor system, is reported. Almost complete conversion (99.4 %) of octanoic acid was achieved, with a remarkably high selectivity to octanol (93.0 %), when using specific reaction conditions (300°C, a weight hourly space velocity (WHSV) of 2 h?1, and 30 atm H2). Characterizations of the catalysts by BET, CO pulse chemisorption, ICP-AES, XRD, XPS and STEM-EDS revealed that the addition of Sn to Ru/ZnO resulted in the formation of a Ru3Sn7 alloy phase as well as SnOx. Comparison with Ru/ZnO catalyst gives an insight that the presence of Ru3Sn7 alloy was most likely the active site and it significantly improved the hydrogenation activity and selectivity to octanol. The SnOx and ZnO favored the formation of octyl octanoate by esterification of the formed octanol and octanoic acid, although it was successfully suppressed by optimizing the reaction conditions. Long-term stability tests revealed that RuSn/ZnO retained its activity for 1000 h with no coke formation. This study reveals the potential of RuSn/ZnO for the valorization of medium-chain fatty acids into value-added chemicals.
Dehydrogenative alcohol coupling and one-pot cross metathesis/dehydrogenative coupling reactions of alcohols using Hoveyda-Grubbs catalysts
?zer, Halenur,Arslan, Dilan,?ztürk, Bengi ?zgün
, p. 5992 - 6000 (2021/04/12)
In this study,in situformed ruthenium hydride species that were generated from Grubbs type catalysts are used as efficient catalysts for dehydrogenative alcohol coupling and sequential cross-metathesis/dehydrogenative coupling reactions. The selectivity of Grubbs first generation catalysts (G1) in dehydrogenative alcohol coupling reactions can be tuned for the ester formation in the presence of weak bases, while the selectivity can be switched to the β-alkylated alcohol formation using strong bases. The performance of Hoveyda-Grubbs 2nd generation catalyst (HG2) was improved in the presence of tricyclohexylphosphine for the selective synthesis of ester derivatives with weak and strong bases in quantitative yields. Allyl alcohol was used as self and cross-metathesis substrate for the HG2 catalyzed sequential cross-metathesis/dehydrogenative alcohol coupling reactions to obtain γ-butyrolactone and long-chain ester derivatives in quantitative yields.
Aerobic oxidation and oxidative esterification of alcohols through cooperative catalysis under metal-free conditions
Karimi, Babak,Ghahremani, Mina,Vali, Hojatollah,Ciriminna, Rosaria,Pagliaro, Mario
supporting information, p. 8897 - 8900 (2021/09/10)
The ABNO@PMO-IL-Br material obtained by anchoring 9-azabicyclo[3.3.1]nonane-3-oneN-oxyl (keto-ABNO) within the mesopores of periodic mesoporous organosilica with bridged imidazolium groups is a robust bifunctional catalyst for the metal-free aerobic oxidation of numerous primary and secondary alcohols under oxygen balloon reaction conditions. The catalyst, furthermore, can be successfully employed in the first metal-free self-esterification of primary aliphatic alcohols affording valued esters.
Carboxylic Acid Reductase Can Catalyze Ester Synthesis in Aqueous Environments
Pongpamorn, Pornkanok,Kiattisewee, Cholpisit,Kittipanukul, Narongyot,Jaroensuk, Juthamas,Trisrivirat, Duangthip,Maenpuen, Somchart,Chaiyen, Pimchai
supporting information, p. 5749 - 5753 (2021/02/01)
Most of the well-known enzymes catalyzing esterification require the minimization of water or activated substrates for activity. This work reports a new reaction catalyzed by carboxylic acid reductase (CAR), an enzyme known to transform a broad spectrum of carboxylic acids into aldehydes, with the use of ATP, Mg2+, and NADPH as co-substrates. When NADPH was replaced by a nucleophilic alcohol, CAR from Mycobacterium marinum can catalyze esterification under aqueous conditions at room temperature. Addition of imidazole, especially at pH 10.0, significantly enhanced ester production. In comparison to other esterification enzymes such as acyltransferase and lipase, CAR gave higher esterification yields in direct esterification under aqueous conditions. The scalability of CAR catalyzed esterification was demonstrated for the synthesis of cinoxate, an active ingredient in sunscreen. The CAR esterification offers a new method for green esterification under high water content conditions.
A study of the mechanism of triglyceride hydrodeoxygenation over alumina-supported and phosphatized-alumina-supported Pd catalysts
Barthos, Róbert,Domján, Attila,Hancsók, Jen?,Lónyi, Ferenc,Mihályi, Magdolna R.,Novodárszki, Gyula,Solt, Hanna E.,Valyon, József,Vikár, Anna
, p. 67 - 79 (2021/10/04)
The mechanism of catalytic hydrodeoxygenation (HDO) of fats, vegetable oils, and fatty acids was studied using alumina-supported Pd catalysts and tricaprylin and valeric acid as model reactants. The chemistry of fatty acid/catalyst interaction was studied by quasi-operando Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS). The Pd/γ–Al2O3 catalyst showed good activity in the hydrogenolysis reaction of the ester bonds to convert tricaprylin to caprylic acid, but they were of poor activity in the consecutive hydrodeoxygenation (HDO) of the acid to paraffin. The surface modification of the support alumina by phosphate groups significantly increased the HDO activity of the Pd catalyst and, consequently, the paraffin yield. The activity change was accounted partly for the partial replacement of the weak base Al–OH groups by weak acid P–OH groups but mainly for the partial elimination of Lewis acid (Al⊕) – Lewis base (O?) pair sites on the surface of the support. Both surface Al–OH and P–OH groups were shown to participate in the reaction with carboxylic acid and formed bidentate surface carboxylate species, which further reacted with hydrogen to give paraffin. Carboxylates of less basic surface sites were found to be more prone to HDO reaction than those of strong base sites. Monodentate carboxylates, formed on Al⊕ O? pair sites were of low reactivity. Phosphatizing eliminated most of the Lewis type acid-base pair sites, therefore, reactive bidentate carboxylates represented the most abundant surface intermediate (MASI) during the HDO reaction of triglyceride. The hydroxyl coverage of the carboxylated surface was shown to become somewhat higher under steady-state reaction conditions. The increased hydroxyl coverage implies that C–O bond hydrogenolysis of the surface carboxylate proceeds, regenerating OH groups and forming aldehyde that could be intermediate of paraffin formation.
