Silica-supported gold nanoparticles catalyzed one-pot, tandem aerobic oxidative cyclization reaction for nitrogen-containing polyheterocyclic compounds

Abstract

A silica-supported gold nanoparticle catalyst AuNPs/SiO 2 (A) has been prepared by deposition of insitu synthesized gold nanoparticles (AuNPs) onto the surface of silica. A simple method that uses A as the catalyst and oxygen as the oxidant is effective for oxidative cyclization of anilines with aldehydes to form quinolines in a one-pot reaction (20examples; product yields up to 95%). The "AuNPs/SiO 2+O 2" protocol is applicable to the synthesis of nitrogen-containing polyheterocyclic compounds in good to excellent product yields by using bulky polycyclic anilines as the starting materials (10examples; product yields up to 96%). The A catalyst can be easily recovered by centrifugation and reused for seven consecutive runs without significant loss of catalytic activity. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.