PALLADIUM COMPLEX-CATALYZED INTERMOLECULAR REDUCTIVE N-HETEROCYCLIZATION - NOVEL SYNTHESIS OF QUINAZOLINE DERIVATIVES FROM 2-NITROBENZALDEHYDE OR 2-NITROPHENYL KETONES WITH FORMAMIDE

A combination of the palladium complex PdCl2(PPh(3)) with MoCl5 shows a high catalytic activity for the intermolecular reductive N-heterocyc lization of 2-nitrobenzaldehyde or 2-nitrophenyl ketones with formamid e to give the corresponding quinazoline derivatives in moderate yields . For example, in the reaction of 2-nitrobenzaldehyde with formamide, quinazoline was obtained in 46% yield. We assume that the present reac tion proceeds via an active nitrene intermediate which would be genera ted by selective deoxygenation of nitro group by carbon monoxide.