31197-64-5Relevant academic research and scientific papers
A general and simple synthesis of phenylglyoxylic esters via the oxidation of mandelic esters with ammonium chlorochromate adsorbed on alumina
Zhang, Gui-Sheng,Gong, Hui
, p. 3149 - 3153 (1999)
A general method for preparation of phenylglyoxylic esters by oxidation of mandelic esters with readily available ammonium chlorochromate adsorbed on alumina is described.
Metal-Free Oxidative Esterification of Ketones and Potassium Xanthates: Selective Synthesis of α-Ketoesters and Esters
Luo, Xianglin,He, Runfa,Liu, Qiang,Gao, Yanping,Li, Jingqing,Chen, Xiuwen,Zhu, Zhongzhi,Huang, Yubing,Li, Yibiao
, p. 5220 - 5230 (2020/05/18)
A novel and efficient oxidative esterification for the selective synthesis of α-ketoesters and esters has been developed under metal-free conditions. In the protocol, various α-ketoesters and esters are available in high yields from commercially available ketones and potassium xanthates. Mechanistic studies have proven that potassium xanthate not only promotes oxidative esterification but also provides an alkoxy moiety for the reaction, which involves the cleavage and reconstruction of C-O bonds.
Controllable chemoselectivity in the coupling of bromoalkynes with alcohols under visible-light irradiation without additives: Synthesis of propargyl alcohols and α-ketoesters
Ni, Ke,Meng, Ling-Guo,Ruan, Hongjie,Wang, Lei
supporting information, p. 8438 - 8441 (2019/07/22)
The chemoselectivity of visible-light-induced coupling reactions of bromoalkynes with alcohols can be controlled by simple changes to the reaction atmosphere (N2 or O2). A N2 atmosphere favours propargyl alcohols via a direct C-C coupling process, whereas an O2 atmosphere results in the generation of α-ketoesters through the oxidative CC/C-O coupling pathway.
CuCl/TMEDA/nor-AZADO-catalyzed aerobic oxidative acylation of amides with alcohols to produce imides
Kataoka, Kengo,Wachi, Keiju,Jin, Xiongjie,Suzuki, Kosuke,Sasano, Yusuke,Iwabuchi, Yoshiharu,Hasegawa, Jun-Ya,Mizuno, Noritaka,Yamaguchi, Kazuya
, p. 4756 - 4768 (2018/06/07)
Although aerobic oxidative acylation of amides with alcohols would be a good complement to classical synthetic methods for imides (e.g., acylation of amides with activated forms of carboxylic acids), to date, there have been no reports on oxidative acylation to produce imides. In this study, we successfully developed, for the first time, an efficient method for the synthesis of imides through aerobic oxidative acylation of amides with alcohols by employing a CuCl/TMEDA/nor-AZADO catalyst system (TMEDA = teramethylethylendiamine; nor-AZADO = 9-azanoradamantane N-oxyl). The proposed acylation proceeds through the following sequential reactions: aerobic oxidation of alcohols to aldehydes, nucleophilic addition of amides to the aldehydes to form hemiamidal intermediates, and aerobic oxidation of the hemiamidal intermediates to give the corresponding imides. This catalytic system utilizes O2 as the terminal oxidant and produces water as the sole by-product. An important point for realizing this efficient acylation system is the utilization of a TMEDA ligand, which, to the best of our knowledge, has not been employed in previously reported Cu/ligand/N-oxyl systems. Based on experimental evidence, we consider that plausible roles of TMEDA involve the promotion of both hemiamidal oxidation and regeneration of an active CuII-OH species from a CuI species. Here promotion of hemiamidal oxidation is particularly important. Employing the proposed system, various types of structurally diverse imides could be synthesized from various combinations of alcohols and amides, and gram-scale acylation was also successful. In addition, the proposed system was further applicable to the synthesis of α-ketocarbonyl compounds (i.e., α-ketoimides, α-ketoamides, and α-ketoesters) from 1,2-diols and nucleophiles (i.e., amides, amines, and alcohols).
I 2 /TBHP-Promoted Approach to α-Keto Esters from Trifluoromethyl β-Diketones and Alcohols via C-C Bond Cleavage
Shao, Tongle,Fang, Xiang,Zhou, Jun,Jin, Chen,Yang, Xueyan,Wu, Fanhong
supporting information, p. 2018 - 2023 (2017/09/13)
A metal-free oxidative coupling reaction of trifluoromethyl β-diketones with alcohols for the synthesis of α-keto esters in good to excellent yields has been developed. Preliminary mechanistic studies suggest that an I 2 /TBHP promoted sequential iodination, C-C bond cleavage, C-O bond formation and oxidation pathway is involved in this reaction.
Chiral cobalt-catalyzed enantioselective aerobic oxidation of α-hydroxy esters
Alamsetti, Santosh Kumar,Sekar, Govindasamy
supporting information; experimental part, p. 7235 - 7237 (2010/12/24)
A chiral cobalt-catalyzed enantioselective aerobic oxidative kinetic resolution of (±)-α-hydroxy esters, using molecular oxygen as a sole oxidant, is reported and a maximum of selectivity factor (s) 31.9 was achieved with >99% enantiomeric excess for unreacted α-hydroxy esters.
Baker's Yeast-Mediated Reductions of α-Keto Esters and an α-Keto-β-Lactam. Two Routes to the Paclitaxel Side Chain
Kayser, Margaret M.,Mihovilovic, Marko D.,Kearns, Jeff,Feicht, Anton,Stewart, Jon D.
, p. 6603 - 6608 (2007/10/03)
Baker's yeast (Saccharomyces cerevisiae) has been used to reduce a series of alkyl esters derived from pyruvate and benzoylformate. Both the yield and enantioselectivities of these reductions were maximized when methyl esters were used, and the (R)-alcohols were isolated in all instances. Yeast-mediated ester hydrolysis was a significant side reaction for products derived from long-chain alcohols. In the case of ethyl benzoylformate, the addition of methyl vinyl ketone increased the enantioselectivity of the reduction. These reductions were applied to two syntheses of the paclitaxel C13 side chain [(2R,3S)-N-benzoyl-3-phenylisoserine]. In the first, a racemic α-keto-β-azido ester was reduced by whole cells of Baker's yeast to afford a diastereomeric mixture in which the desired product predominated and could be isolated chromatographically. In the second, an easily synthesized α-keto-β-lactam was reduced by yeast cells to afford the desired eis isomer as well as the undesired trans diastereomer. Substituting a yeast strain deficient in fatty acid synthase in this reduction suppressed formation of the trans diastereomer. These results suggest that a single enzyme is responsible for both the D- and L-cis-alcohols resulting from reduction of the α-keto-β-lactam. All of the yeast strains used in this project are available commercially, and these biocatalytic reductions require only common laboratory equipment.
