描述了C 2对称的手性O,N,N,O-四齿2,2-联吡啶二醇二醇丙烷配体的合成。Mukaiyama–Michael反应被用作合成2,2-联吡啶丙烷9的重要反应。在合成的配体中,配体11在二乙基锌和各种醛类化合物中均表现出出色的手性诱导(至多97%ee)。对于本催化体系,不需要在二乙基锌加成反应中使用额外的路易斯酸,例如Ti(O i Pr)4。
Synthesis of Chiral Pyridylphenols for the Enantioselective Addition of Diethylzinc to Aldehydes
作者:Pei-Shan Wu、Chinpiao Chen
DOI:10.1002/jccs.201100474
日期:2012.6
Chiral 8‐substituted 2‐(8,10,10‐trimethyl‐6‐aza‐tricyclo[7.1.1.02,7]undeca‐2(7),3,5‐trien‐5‐yl)‐phenols were prepared from a high enantiopurity (>97% ee) of (1R)‐(+)‐α‐pinene, and assessed in the enantioselectiveaddition of diethylzinc to substituted benzaldehydes, giving the (S)‐alcohols with enantiomeric excess ranging from 33% to 89%. Interestingly, in all cases, except for those of ortho‐chlorobenzaldehyde