Catalytic Heteroannulation for the Synthesis of Quinoline‐4‐Carboxamides Bearing Axial Chirality

Abstract

AbstractAn iron(III) triflate catalyzed Friedländer‐type heteroannulation of 2‐(2‐aminophenyl)‐N,N‐dialkyl‐2‐oxoamides with α‐methylene carbonyl derivatives has been established, allowing facile access to a range of biologically interesting quinoline‐containing tertiary amides in good yields. Investigations into the configurational stability of products led to the identification of a new type of stable axially chiral quinoline‐4‐carboxamide bearing a sterically demanding phenylsulfonyl C3‐substituent. Subsequently, an enantioselective catalytic variant was attempted. The employment of copper(II) catalysis using a chiral bisoxazoline ligand was found to be capable of providing moderate enantiocontrol.magnified image