Design of Organocatalysts for Asymmetric Direct Syn-Aldol Reactions
作者:Xiao-Ying Xu、Yan-Zhao Wang、Liu-Zhu Gong
DOI:10.1021/ol701798x
日期:2007.10.1
Two new organocatalysts 3a and 3b, derived from L-leucine and (S)-beta-amino alcohols that were prepared from L-valine, were designed and afforded the direct syn-aldol reactions of a wide scope of aldehydes with various ketones with an excellent diastereomeric ratio of up to >20/1 and enantioselectivities of up to 99% ee.