Highly enantioselective phosphination and hydrophosphonylation of azomethine imines: using chiral squaramide as a hydrogen bonding organocatalyst†
Abstract
Enantioselective phosphination and hydrophosphonylation reactions between azomethine imines and diarylphosphine oxides or dialkyl phosphites were respectively developed by the use of a chiral squaramide as the hydrogen bonding organocatalyst, which afforded two types of phosphorus containing product in high yields with good to excellent enantioselectivities.