Asymmetric Diels-Alder Reaction of α-Substituted and β,β-Disubstituted α,β-Enals via Diarylprolinol Silyl Ether for the Construction of All-Carbon Quaternary Stereocenters
作者:Yujiro Hayashi、Bojan P. Bondzic、Tatsuya Yamazaki、Yogesh Gupta、Shin Ogasawara、Tohru Taniguchi、Kenji Monde
DOI:10.1002/chem.201602345
日期:2016.10.24
Diels–Alder reaction of α‐substituted acrolein proceeds in the presence of the trifluoroacetic acid salt of trifluoromethyl‐substituted diarylprolinol silyl ether to afford the exo‐isomer with both excellent diastereoselectivity and high enantioselectivity. In the Diels–Alder reaction of a β,β‐disubstituted α,β‐unsaturated aldehyde, good exo‐selectivity and excellent enantioselectivity was obtained when the
α-取代的丙烯醛的不对称Diels-Alder反应在三氟甲基取代的二芳基脯氨醇甲硅烷基醚的三氟乙酸盐存在下进行,从而提供具有优异的非对映选择性和高对映选择性的外向异构体。在β,β-二取代的α,β-不饱和醛的Diels-Alder反应中,当将三氟甲基取代的二芳基脯氨醇的大体积三异丙基甲硅烷基醚的高氯酸盐用作有机催化剂时,可获得良好的exo-选择性和出色的对映选择性。水的存在。在这两种情况下,全碳四元立体中心都是对映选择性地构建的。