Asymmetric synthesis of 2,3-dihydroquinolin-4-one derivatives catalyzed by a chiral bisguanidium salt

Abstract

Worth its salt: An orgnaocatalytic asymmetric intramolecular aza-Michael reaction and one-pot bromination reaction of activated α,β-unsaturated ketones have been realized using a chiral bisguanidium salt. Optically enriched 2-aryl- and 2-alkyl-substituted dihydroquinones and brominated dihydroquinones could be obtained (up to 99% yield and 99% ee for the aza-Michael reaction; and up to 95% yield, 96:4 d.r., and 95% ee for the bromination reaction).