Abstract
3-Carbethoxy-5,7-dimethoxycoumarin (2) underwent Michael addition and addition-cyclization of some active methylene compounds under different reaction conditions to give the adducts (3-7). Addition of phenylmagnesium bromide onto (2) yielded the tertiary alcohol (8). Addition of ammonia derivatives on (2) afforded the 3-carboxamides (9a-c) and azine (10). Furthermore, alcoholysis and hydrolysis yielded the coumarins (11a-c).