Synthesis of Quinazolinones from Alcohols via Laccase-Mediated Tandem Oxidation

This paper describes the synthesis of quinazolinones via a tandem reaction using the laccase-mediator system under mild conditions. The procedure involved the laccase-catalyzed oxidation of alcohols to the corresponding aldehydes, followed by cyclocondensation with isatoic anhydride and a number of amines to afford 2,3-dihydroquinazolin-4(1H)-ones, which were further oxidized to quinazolinones in useful yields. The use of an enzyme as the catalyst, O2 as an environmentally friendly oxidant, and a citrate buffer as the green solvent represents a novel and efficient approach for the one-pot synthesis of quinazolinones.