Catalytic enantioselective intermolecular reductive aldol reaction to ketones
- 作者：Dongbo Zhao ; Kounosuke Oisaki ; Motomu Kanai and Masakatsu Shibasaki
- 关键词：Asymmetric catalysis ; Aldol reaction ; Ketones ; Copper fluoride ; Conjugate reduction ; Multi-component reaction
- 刊名：Tetrahedron Letters
- 出版年：2006
- 期刊代码：109_00404039
- 类别：ch
- 出版时间：27 February 2006
- 卷：47
- 期：9
- 页码：1403-1407
- 文件大小：130 K
摘要
We describe the first example of a catalytic enantioselective intermolecular reductive aldol reaction. Three types of reactions were studied: (1) reactions between acetophenone and methyl acrylate; (2) reactions between symmetric ketones and β-substituted α,β-unsaturated esters; and (3) reactions between acetophenone derivatives and an allenic ester. Although only moderate enantioselectivity was obtained in the first reaction type, high to excellent enantioselectivity was realized in the enantio-induction at the α-position in the second reaction type and at the δ-position in the third reaction type. Specifically, the third reaction type afforded the corresponding tertiary alcohols with up to 99%ee. Pre-activation of the nucleophile by silyl enolate formation is not necessary in these one-pot catalytic enantioselective reductive aldol reactions.