Photoinduced Reductive Elimination of Nitro Groups from Vicinal Dinitro Compounds

Abstract

Irradiation of 9, 9'-dinitro-9, 9'-bifluorenyls [1a-c] and dl- and meso-1, 2-dinitro-1, 2-diphenylethane (dl-[Id] and meso-[1d]) in DMF with a high-pressure Hg lamp caused reductive elimination of the nitro groups via a radical chain (ERc) mechanism to give the corresponding olefins [2a-d] which in turn gave 9, 9'-bifluorenyls [3a-c] and phenanthrene [4], respectively, on further irradiation. The aliphatic vicinal dinitro compounds, 1, 1'dinitro-1, 1'-bicychohexyl [1e] and 2, 3-dinitro-2, 3-dimethylbutane [1f], did not photoreact in DMF or cyclohexane under similar reaction conditions.