(R)-(+)-N-Methylbenzoguanidine ((R)-NMBG) catalyzed kinetic resolution of racemic secondary benzylic alcohols with free carboxylic acids by asymmetric esterification
作者:Kenya Nakata、Isamu Shiina
DOI:10.1039/c1ob05736g
日期:——
the kineticresolution of racemic secondary benzylic alcohols in the presence of achiral carboxylicacids and pivalic anhydride. The use of a tertiary amine in this reaction is not necessary to attain good chemical yields of the products. It was determined that diphenylacetic acid could be employed as the most suitable acyl donor for achieving a high enantioselectivity for the kineticresolution of
2,2-Disubstituted Propionic Anhydrides: Effective Coupling Reagents for the Kinetic Resolution of Secondary Benzylic Alcohols Using BTM
作者:Isamu Shiina、Kenya Nakata、Masuhiro Sugimoto、Yu-suke Onda、Takashi Iizumi、Keisuke Ono
DOI:10.3987/com-08-s(f)75
日期:——
variety of opticallyactive benzylic alcohols possessing aliphatic substituents at the C-1 position are produced by the kinetic resolution of racemic secondary alcohols using free carboxylicacids with 2,2-disubstituted propionic anhydrides and (+)-benzotetramisole (BTM). Evaluation of the efficiency of this asymmetric esterification using several anhydrides derived from aliphatic carboxylicacids were carried
The first asymmetric esterification of free carboxylic acids with racemic alcohols using benzoic anhydrides and tetramisole derivatives: an application to the kinetic resolution of secondary benzylic alcohols
作者:Isamu Shiina、Kenya Nakata
DOI:10.1016/j.tetlet.2007.09.135
日期:2007.11
non-substituted benzoic anhydride is used as a coupling reagent, the resulting opticallyactivealcohols are obtained with high selectivities. This protocol directly produces chiral carboxylic esters from free carboxylic acids and racemic secondary alcohols by utilizing the trans-acylation process to generate mixed anhydrides from acid components and benzoic anhydride derivatives under the influence of chiral