Laccase‐Based Oxidative Catalytic Systems for the Aerobic Aromatization of Tetrahydroquinazolines and Related N‐Heterocyclic Compounds under Mild Conditions

Abstract

In this work, for the first time, laccase (metalloenzyme)/3,5‐di‐tert‐butylcatechol (DTBC) as a new class of bioinspired quinone‐based cooperative catalytic oxidation system and laccase/2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPO) catalyst system were used for the aerobic oxidative synthesis of 2‐substituted quinazolines through cascade reaction of structurally divers aldehydes with 2‐aminobenzylamine. The products were obtained in good to high yields in phosphate buffer (0.1 m, 12.5 mL, pH = 4.5) and acetonitrile (4 vol.‐%) mixture as solvent at 45 °C. Other N‐heterocycles are also successfully oxidized to their aromatic counterparts.