Synthesis and Transformations of 2- and 4-(2-Methylquinolin-4-ylamino)benzoic Acids and Ethyl 4-(2-Methylquinolin-4-ylamino)benzoates and Their Fluorescent Properties

摘要

2- and 4-(2-Methylquinolin-4-ylamino)benzoic acids and ethyl 4-(2-methylquinolin-4-ylamino)-benzoates having a substituent in the 6(8)-position of the quinoline ring were synthesized by reaction of the corresponding substituted 4-chloro-2-methylquinolines with 2- and 4-aminobenzoic acids and ethyl 4-amino-benzoate. Intramolecular cyclization of 2-(2-methylquinolin-4-ylamino)benzoic acids in concentrated sulfuric acid gave 7-hydroxy-6-methyldibenzo[b,h]naphthyridines, and ethyl 4-(2-methylquinolin-4-ylamino)ben-zoates were converted into 4-(2-methylquinolin-4-ylamino)benzoic acids by alkaline hydrolysis.