METHOD FOR PRODUCING OPTICALLY ACTIVE ESTER AND METHOD FOR PRODUCING OPTICALLY ACTIVE CARBOXYLIC ACID
申请人:Shiina Isamu
公开号:US20100234610A1
公开(公告)日:2010-09-16
Disclosed is a method for producing an optically active ester by highly selectively esterifying one enantiomer of a racemic carboxylic acid, while producing an optically active carboxylic acid which is the other enantiomer. An optically active ester is produced while producing an optically active carboxylic acid at the same time by reacting a racemic carboxylic acid with a specific alcohol or phenol derivative in the presence of benzoic anhydride or a derivative thereof and a catalyst such as tetramisole or benzotetramisole, thereby selectively esterifying one enantiomer of the racemic carboxylic acid.
Method for manufacturing optically active carboxylic acid ester
申请人:Shiina Isamu
公开号:US09315442B2
公开(公告)日:2016-04-19
A method that manufacturers an optically active carboxylic acid ester at high yield and high enantioselectivity is provided. An optically active carboxylic acid ester is manufactured at high yield and high enantioselectivity by reacting a racemic carboxylic acid and a specific alcohol or phenol derivatives in a polar solvent having a dipole moment of 3.0 or higher in the presence of an acid anhydride and an asymmetric catalyst, esterifying one enantiomer of the racemic carboxylic acid at high selectivity, and increasing the amount of esterified carboxylic acid by racemizing the optically active carboxylic acid which is the other enantiomer not used in esterification.
Kinetic Resolution of Racemic α-Arylalkanoic Acids with Achiral Alcohols via the Asymmetric Esterification Using Carboxylic Anhydrides and Acyl-Transfer Catalysts
enantioselective coupling reaction betweenracemic carboxylic acids and a novel nucleophile, bis(alpha-naphthyl)methanol, to give the corresponding esters with high ee's. This protocol was successfully applied to the production of nonracemic nonsteroidal anti-inflammatory drugs from racemiccompounds utilizing the transacylation process to generate the mixed anhydrides from the acid components with the suitable carboxylic
通过使用非手性醇、芳香族或脂肪族羧酸酐和手性酰基转移催化剂对外消旋 α-取代羧酸进行动力学拆分,可以生产多种光学活性羧酸酯。4-甲氧基苯甲酸酐 (PMBA) 或新戊酸酐与改性苯并四甲醚型催化剂 ((S)-β-Np-BTM) 的组合对于促进外消旋羧酸与新型亲核试剂之间的对映选择性偶联反应最有效, 双(α-萘基)甲醇,得到相应的具有高 ee 的酯。
Di(1‐naphthyl) methanol ester of carboxylic acids for absolute stereochemical determination
The absolute stereochemistry of chiral carboxylicacids is determined as a di(1‐naphthyl)methanol ester derivative. Computational scoring of conformations favoring either P or M helicity of the naphthyl groups, capable of exciton‐coupled circular dichroic coupling, leads to a predicted stereochemistry for the derivatized carboxylicacids.