Catalyst-controlled selective mono-/dialkylation of 2-aryl-4(3H)-quinazolinones

Abstract

Catalyst-controlled selective mono-/dialkylation of 2-aryl-4(3H)-quinazolinones with α-diazotized Meldrum's acid has been achieved successfully via a metal carbene migratory insertion process. With a Cp*Rh(III) catalyst, monoalkylation compounds are the predominant products while a Cp*Ir(III) catalyst selectively affords dialkylation products. Furthermore, these developed methods have good functional group tolerance with a low catalyst loading unprecedentedly.