Work

Catalyzed Asymmetric Michael Additions of 1‐Pyrroline Esters with β‐Fluoroalkyl Alkenyl Imides and Azodicarboxylates

Year: 2025

Type: article

Abstract: The asymmetric Michael addition reactions of 1‐pyrroline esters with β‐fluoroalkyl alkenyl imides and dialkyl azodicarboxylates catalyzed by the AgOAc/Ph‐phosferrox or CuOAc/(R)‐BINAP complex have been developed. A series of chiral 1,5,5‐trisubstituted pyrroline ester derivatives have been obtained in 53%–90% yields with 80%–99% ee’s and all > 20:1 dr. The gram‐scale synthesis and synthetic application of the chiral trifluoromethylated 1‐pyrroline adducts were exhibited: the pyrrolizidin‐3‐one analogue was first synthesized with 94% ee and > 20:1 dr through two steps of hydrolysis and reductive cyclization; the pyrrolidine and lactam derivatives were also successfully provided under the reducing conditions of NaBH3CN and Pd/C─H2, respectively.

Source: Chemistry - A European Journal

DOI: 10.1002/chem.202501256