Dynamic Kinetic Resolution with Enantioselective Borohydride Reduction Catalyzed by Optically Active β-Ketoiminato Cobalt(II) Complexes: Highly Diastereo- and Enantioselective Preparation of Optically Active<i>anti</i>-Aldol Compounds
Opticallyactive anti-2-alkyl-3-hydroxy esters were stereoselectively obtained from the corresponding 2-alkyl-3-keto esters using enantioselective borohydride reduction along with dynamic kinetic resolution in the presence of opticallyactive β-ketoiminato cobalt complex catalysts. The reduction system provided an alternative preparation for anti-aldol compounds with high diastereo- and enantioselectivities
Surface-Mediated Solid Phase Reaction. IX. A Convenient Procedure for Aldol Reaction of Ketene Silyl Acetals with Aldehydes on the Solid Surface of Alumina
作者:Brindaban C. Ranu、Manika Saha、Sanjay Bhar
DOI:10.1080/00397919708005012
日期:1997.9
The aldol reaction of ketene silyl acetals with aldehydes proceeds efficiently on the solid surface of alumina impregnated with anhydrous zinc chloride under sonication providing aldol products in high yields and with good stereoselectivity.
Enantioselective Borohydride Reduction Catalyzed by Optically Active Cobalt Complexes
作者:Tohru Yamada、Takushi Nagata、Kiyoaki D. Sugi、Kiyotaka Yorozu、Taketo Ikeno、Yuhki Ohtsuka、Daichi Miyazaki、Teruaki Mukaiyama
DOI:10.1002/chem.200304794
日期:2003.9.22
enantioselective borohydride reduction of aromatic ketones or imines to the corresponding alcohols was developed in the presence of a catalytic amount of an opticallyactive cobalt(II) complex catalyst. This enantioselective reduction is carried out using a precisely premodified borohydride with alcohols such as tetrahydrofurfuryl alcohol, ethanol and methanol. High optical yields are obtained by choosing