A Simple Primary−Tertiary Diamine−Brønsted Acid Catalyst for Asymmetric Direct Aldol Reactions of Linear Aliphatic Ketones
作者:Sanzhong Luo、Hui Xu、Jiuyuan Li、Long Zhang、Jin-Pei Cheng
DOI:10.1021/ja069372j
日期:2007.3.1
regio- and diastereoselectivity and enantioselectivity under ambient temperature. Significantly, the reactions accommodate the synthetically important but challenging substrates, such as linear aliphatic ketones, with high regioselectivity and unprecedented syn diastereoselectivity. These results are in sharp contrast with the secondary amine mediated similar reactions wherein anti diastereoselectivity
与已充分探索的带有仲胺的烯胺催化相比,开发高效的基于烯胺的伯胺催化剂直到最近仍然是一个难以捉摸的目标。我们在本文中提出了一种简单的手性伯-叔二胺 1d 与 TfOH 结合用作有效的基于烯胺的伯胺催化剂。1d-TfOH催化体系可以有效催化不对称直接醛醇反应,底物范围广,在环境温度下具有高区域选择性和非对映选择性以及对映选择性。值得注意的是,这些反应适应了合成上重要但具有挑战性的底物,例如线性脂肪族酮,具有高区域选择性和前所未有的顺式非对映选择性。