Asymmetric reductions of prochiral ketones with B-3-pinanyl-9-borabicyclo [3.3. 1] nonane (Alpine-Borane) at elevated pressures

…, JI McLoughlin, J Gabriel

Index: Midland, M. Mark; McLoughlin, Jim I.; Gabriel, Josef Journal of Organic Chemistry, 1989 , vol. 54, # 1 p. 159 - 165

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Citation Number: 59

Abstract

The reduction of unhindered ketones, such as acetylenic ketones, with B-3-pinanyl-9- borabicyclo [3.3. l] nonane (Alpine-Borane, prepared by hydroboration of a-pinene with 9- BBN) provides a simple means of forming chiral, nonracemic alcohols of known absolute configuration in high enantiomeric purity. A dehydroboration-reduction mechanism leading to racemic alcohol is believed to be responsible for erosion of the enantiomeric efficiency ...