SYNTHETIC COMMUNICATIONS, v. 45, NO 6, Page. 758-776
A simple method to synthesize N-heteropolycyclic quinazolinones was developed including Knoevenagel condensation of quinazolines and aldehydes and Friedel-Craft alkylation as key steps. Knoevenagel reaction of 2-methyl-3-phenylquinazolin-4(3H)-one proceeded smoothly under a basic condition and subsequent Friedel-Craft alkylation with BrOnsted acid gave the N-heteropolycyclic quinazolinones in good yields. Furthermore, these new polycyclic compounds were converted into organic molecules having a long -conjugation system by treatment of 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) to utilize them as organic dyes.