Cu-Nanoparticles: efficient catalysts for the oxidative cyclization of Schiffs’ bases

Cu-Nanoparticles provide an efficient catalysis for the synthesis of 2-arylbenzoxazoles by the coupling of aromatic or heteroaromatic aldehydes with 2-aminophenol though the oxidative cyclization of the Schiffs’ bases using 10 mol % of the Cu-nanoparticles in the presence of K2CO3 in MeOH. This method avoids the use of metal oxide or organic oxidizing agents, namely, DDQ or strong acids such as polyphosphoric acid or boric acid.