A variety of optically active carboxylic esters were produced by kinetic resolution of racemic carboxylic acids by using achiral alcohols, benzoic anhydrides, and Birman's tetramisole‐type catalysts. Bis(α‐naphthyl)methanol is a very effective reagent for producing the corresponding esters with high ee values in the presence of 4‐methoxybenzoic anhydride (PMBA) as the coupling reagent by promotion of benzotetramisole derivatives (BTM, α‐Np‐BTM, and β‐Np‐BTM). This protocol directly provides chiral carboxylic esters from free carboxylic acids and achiral alcohols by utilizing a transacylation process to generate the mixed anhydrides from the acid components with benzoic anhydride derivatives in the presence of chiral catalysts.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

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A widely applicable method is developed via generation of mixed anhydrides followed by reaction with bis(9‐phenanthryl)methanol in the presence of (+)‐benzotetramisole as the catalyst.

Alcohols Q 02302,2-Disubstituted Propionic Anhydrides: Effective Coupling Reagents for the Kinetic Resolution of Secondary Benzylic Alcohols Using BTM. -Not only Piv 2 O is a widely usable reagent to provide the esters (IV) with high enantiomeric excess in the presence of benzotetramisole, but other kinds of anhydrides, e.g. Bz2O, are also applicable as effective coupling reagents for generating optically active esters and alcohols with high ee's under mild conditions. The chiral carboxylic esters (III) are produced directly from the free carboxylic acids (II) and racemic secondary alcohols (I) by utilizing the transacylation process to generate mixed anhydrides from the acid components and sterically hindered carboxylic anhydrides under influence of a chiral catalyst. -(SHIINA*, I.; NAKATA, K.; SUGIMOTO, M.; ONDA, Y.-S.; IIZUMI, T.; ONO,