Photoirradiated and γ-ray-irradiated reactions of manganese(III, IV, V) tetraphenylporphyrins in 2-methyltetrahydrofuran. Reactions of azidomanganese(III) porphyrin

Manganese(III, IV) tetraphenylporphyrins Mn/sup III/(TPP)X(TPP = 5,10,15,20-tetraphenylporphinato; X = I, Br, Cl, N3, NCS, OAc) and Mn/sup IV/(TPP)(OCH3)2 in 2-methyltetrahydrofuran (MeTHF) at room temperature were reduced to yield Mn/sup II/(TPP) by photoirradiation with visible light (440-750 nm) or by γ-ray irradiation. The photoirradiation of Mn/sup III/(TPP)N3 in the rigid matrix at 77 K affords Mn/sup V/(TPP)N. Photochemically stable Mn/sup V/(TPP)N was reduced to Mn/sup II/(TPP) by γ-irradiation at room temperature. γ-irradiation of MeTHF solutions of Mn/sup III/(TPP)X at 77 K causes one-electron reduction to form the constrained complexes [Mn/sup II(TPP)X]-. Warming the matrices after γ-irradiation formed Mn/sup II/(TPP), liberating ligand X-. The near-infrared bands of Mn/sup III/(TPP)X red shift along with the shifts of the bands in the visible region by varying the ligand X. The characteristic bands of the constrained complex [Mn/sup II(TPP)X]- in the near-infrared region red shift in the order X = Cl > Br > 1. The photoirradiation of Cr/sup III/(TPP)N3 with visible light affords Cr/sup V/(TPP)N at room temperature and at 77 K. 39 references, 6 figures, 5 tables