Additives Promote Noyori-type Reductions of a β-Keto-γ-lactam: Asymmetric Syntheses of Serotonin Norepinephrine Reuptake Inhibitors
作者:Nicholas A. Magnus、Bret A. Astleford、Dana L. T. Laird、Todd D. Maloney、Adam D. McFarland、John R. Rizzo、J. Craig Ruble、Gregory A. Stephenson、James P. Wepsiec
DOI:10.1021/jo400589j
日期:2013.6.7
norepinephrine reuptake inhibitor (SNRI) pyrrolidinyl ether 2 was synthesized by employing a dynamic kinetic resolution (DKR) with enantio- and diastereoselective hydogenation on β-keto-γ-lactam 8 to afford β-hydroxy-γ-lactam 9 with 96% ee and 94% de. Reduction of 9 and purification via the dibenzoyl-(l)-tartaric acid diastereomeric salt 16 enriched the ee and de to 100%. While screening hydrogenation
5-羟色胺去甲肾上腺素再摄取抑制剂(SNRI)吡咯烷基醚2通过在β-酮-γ-内酰胺8上进行对映和非对映选择性水合反应的动态动力学拆分(DKR)合成,得到ee为96%的β-羟基-γ-内酰胺9和94%的de。9的还原和通过二苯甲酰基-(1)-酒石酸非对映异构体盐16的纯化使ee和de富集至100%。在使用钌-BINAP催化剂筛选氢化反应体系以制备9的同时,发现添加催化HCl和LiCl可以提高收率。此外,DKR加氢的速率和平衡为8,得到9通过在线NMR和手性HPLC,这表明对映体中的一个研究8被减少更快9比的立构中心的平衡8。