Pyridine-N-oxide catalyzed acylative desymmetrization of bisphenols: access to P-stereogenic phosphinates with low catalyst loadings†
Abstract
A catalytic stereoselective strategy to access P-stereogenic phosphinates through chiral 4-arylpyridine-N-oxide-catalyzed acylative desymmetrization of bisphenols has been reported. In the presence of 0.05 mol% 4-arylpyridine-N-oxide catalyst, chiral P-stereogenic phosphinates were obtained in up to 97% yields and 96% ee under mild conditions for 2 h. A series of chiral phosphorus compounds containing carboxylic acid drug molecules such as gemfibrozil, isoxepac, and indomethacin were synthesized with high yields and high enantioselectivities.