An effective synthesis for syn-β-lactams was achieved using a Rh-catalyzed reductive Mannich-type reaction. A rhodium–hydride complex (Rh–H) derived from diethylzinc (Et2Zn) and a Rh catalyst was used for the 1,4-reduction of an α,β-unsaturated ester to give a Reformatsky-type reagent, which in turn, reacted with an imine to give the syn-β-lactam. Additionally, the reaction was applied to the synthesis of (±)-ezetimibe, a potent β-lactamic cholesterol absorption inhibitor.
通过使用钌催化的还原曼尼希型反应,成功实现了对 syn-β-内酰胺的有效合成。从二乙基锌(Et2Zn)和钌催化剂派生的钌-氢化物络合物(Rh–H)用于α,β-不饱和酯的1,4-还原,以提供类似改革试剂的反应物,后者再与亚胺反应生成 syn-β-内酰胺。此外,该反应还被应用于合成 (±)-依泽替米,这是一种强效的β-内酰胺胆固醇吸收抑制剂。