Molecular-Sieves Controlled Diastereo- and Enantioselectivity: Unexpected Effect in the Organocatalyzed Direct Aldol Reaction
作者:Jun-An Ma、Xiao-Juan Li、Guang-Wu Zhang、Lian Wang、Ming-Qing Hua
DOI:10.1055/s-2008-1072586
日期:2008.5
An efficient asymmetric organocatalyst was developed for the direct aldol reaction between ketones and aldehydes to afford β-hydroxy ketones in high stereoselectivity (anti/syn up to 92:8, ee up to >99%). The key of the success was the use of activated molecular sieves (4 ŠMS), which acted as a water scavenger. The influence of additives such as water or different types of molecular sieves on the reactivity and stereoselectivity of the reaction was also studied.
一种高效的非对称有机催化剂被开发出来,用于酮和醛之间的直接aldol反应,以高立体选择性(anti/syn高达92:8,ee高达>99%)制备β-羟基酮。成功的关键在于使用了活化的分子筛(4 Å MS),其作为水的清除剂。还研究了水分或不同类型分子筛等添加剂对反应活性和立体选择性的影响。