Catalytic enantioselective synthesis of secondary alcohols using C2-symmetric diamino diol ligands
作者:Biao Jiang、Yan Feng、Jian-Feng Hang
DOI:10.1016/s0957-4166(01)00409-8
日期:2001.9
A new class of diamino diols was evaluated as catalytic ligands in the enantioselective borane reduction of aromatic ketones and the enantioselective ethylation of arylaldehydes with diethylzinc. By variation of the substitution pattern on the ketone, e.e.s of up to 94% could be obtained by in situ borane reduction using 0.025 equiv. of the ligand at 35°C in THF. N,N,N′,N′-Tetramethyldiamino diol and
评估了一类新型的二氨基二醇作为芳族酮的对映选择性硼烷还原和芳醛与二乙基锌的对映选择性乙基化的催化配体。通过改变酮上的取代模式,可通过使用0.025当量的原位硼烷还原获得高达94%的ee。35℃下的配体在THF中的摩尔数。N,N,N ′,N′-四甲基二氨基二醇和N,N′-二烷基二氨基二醇用作促进剂,用于将二乙基锌试剂对映选择性地添加到芳醛中,其中使用0.1当量。的Ñ,Ñ,Ñ ',Ñ在将二乙基锌添加到芳醛中时,以'-四甲基二氨基二醇为催化剂可实现高达98%的ee。