Convenient synthesis of 1, 2-dihydroquinoline-3-carboxylic acid and 2H-1-benzothiopyran-3-carboxylic acid derivatives

摘要

A new and efficient method for the preparation of 1, 2-dihydroquinoline-3-carboxylic acid derivatives via a magnesium amide-induced sequential conjugate addition-aldol type condensation reaction between 2-(alkylamino)phenyl ketones and #alpha#, #beta#-unsaturated carboxylic acid derivatives, followed by simple dehydration, is described. The method can be applied to the synthesis of 2H-1-benzothiopyran-3-carboxylic acid derivatives using 2-mercaptobenzophenone in place of 2-(alkylamino)phenyl ketones.