Photoinduced reaction of polyfunctional nitroaromatics: photoreduction versus photosubstitution reaction of nitrobenzylidene malonic derivatives withtriethylamine

Broad band irradiation of nitrobenzylidene malonic derivatives in benzene s olution in the presence of triethylamine leads to two types of photochemica l reactions, photoreduction of the nitro group predominantly, and photosubs titution of the cyano group. The formation of the products is suggested to proceed through a radical ion pair via initial electron transfer, followed by proton transfer, and finally through a sequence of ground state reaction s leading to different products. (C) 1999 Elsevier Science S.A. All rights reserved.