A practical and convenient organocatalytic strategy is developed to provide a direct route to syn-selective aldol products in the presence of water. The siloxy serine organocatalyst mediates the direct aldol reaction of TBSO-protected hydroxyacetone with a variety of aldehydes to provide the aldol products in good yields and enantioselectivities up to 92%.
Asymmetric aldol reaction using a very simple primary amine catalyst: divergent stereoselectivity by using 2,6-difluorophenyl moiety
作者:Yuya Tanimura、Kenji Yasunaga、Kaori Ishimaru
DOI:10.1016/j.tet.2014.02.059
日期:2014.4
Asymmetric aldol reactions of aliphatic ketones or aldehydes with aromatic aldehydes or isatins were catalyzed by a very simple and flexible N-(2,6-difluorophenyl)-L-valinamide. Interestingly, stereochemical course of the reaction of hydroxyacetones or alpha-branched aliphatic aldehydes as aldol donors was different from that of cycloalkanones. (C) 2014 Elsevier Ltd. All rights reserved.
Organocatalytic Asymmetric<i>syn</i>-Selective Direct Aldol Reaction in Ionic Liquid
A practical and recyclable organocatalytic strategy is developed to provide syn-selective aldol products in ionic liquid. The siloxy serine organocatalyst mediates the direct aldol reaction of TBSO-protected hydroxyacetone with a variety of aldehyde to provide the β-hydroxycarbonyl scaffolds in good yields and enantioselectivities up to 94%.