Conversion of 3-Carbethoxy-4-methyl Coumarin Derivatives into Several New Annelated Coumarin Derivatives

摘要

The reaction of ethyl esters of 4-methyl-2-oxo-2H-l-benzo (naphtho) pyran-3-carboxylic acids (1) with aromatic aldehydes in the presence of piperidine yielded 4-styryl-3-carboxami-dopiperidyl coumarin derivatives 4. The reaction of hydrazine hydrate with 1 gave acetophenone hydrozone derivatives 5 and acetophenone azine derivatives 6. The reaction of 1 with primary amines afforded compounds 7―9. And the treatment of la with Grignard reagents afforded 3-aroyl-4-methyl coumarin derivatives 10.