Synthesis of a C2-symmetric chiral bipyridyldiol ligand and its application in the enantioselective addition of diethylzinc to substituted benzaldehydes
作者:Yi-Jing Chen、Rong-Xin Lin、Chinpiao Chen
DOI:10.1016/j.tetasy.2004.09.031
日期:2004.11
suitable catalyst for the enantioselective addition of dialkylzinc to various aromatic aldehydes with asymmetric inductions of up to 99% ee. Importantly, the correlation of Hammett substituent constants and enantiomeric excess, with the electron-donating group at the para-position and the electron-withdrawing group at the meta-position of substituted benzaldehydes were demonstrated to give high enantioselectivity
本文描述了新颖的C 2对称配体的合成,所述C 2对称配体包括中心联吡啶-pine烯衍生的核心和两个官能化的二苯基甲醇亚基。[8'-(羟基-二苯甲基)-10,10,10',10'-四甲基-[5,5'] bi [6-氮杂-三环[7.1.1.0 2,7 ]十一烷基] -2( 7),3,5,2'(7'),3',5'-己烯-8-基]-二苯基甲醇10是用于将二烷基锌对映选择性加成到各种芳族醛中的不对称诱导反应的合适催化剂到99%ee。重要的是,Hammett取代基常数和对映体过量与对位上的给电子基团和间位的吸电子基团的相关性在使用二乙基锌的烷基化反应中,取代苯甲醛的-位被证明具有很高的对映选择性。