Enantioselective Addition of Dialkylzinc Reagents to <i>N</i>-(Diphenylphosphinoyl) Imines Promoted by 2-Azanorbornylmethanols
作者:David Guijarro、Pedro Pinho、Pher G. Andersson
DOI:10.1021/jo9718096
日期:1998.4.1
the workup. Amino alcohol 2b, that gave the best enantioselectivities in the stoichiometric reaction, was also applied in a catalytic process, and ee's up to 85% were achieved using 0.25 equiv of the ligand, which is the highest ee obtained so far using that catalytic amount of the ligand. Addition products 3 could be converted into the free amines 4 without racemization by acidic hydrolysis. The utility
已经制备了一组具有2-氮杂降冰片烯骨架的新的β-氨基醇2,并评估了其作为促进二烷基锌试剂向N-(二苯基膦酰基)亚胺1的对映选择性加成的促进剂。 ee最高可达92%。尽管使用了化学计量的配体,但在后处理期间可以回收约90%的配体。在化学计量反应中具有最佳对映选择性的氨基醇2b也用于催化过程,使用0.25当量的配体可达到ee的85%,这是迄今为止使用该催化量的ee获得的最高ee。配体。加成产物3可以不通过酸水解外消旋地转化为游离胺4。