Photoredox reactivity of copper(II)-3,5-diisopropylsalicylate induced by ligand-to-metal charge transfer excitation of the copper-phenolate chromophore

The electronic spectrum of Cu-II(dps)(2) in CH3CN with dps = 3,5-diisopropylsalicylate shows a ligand field absorption at lambda(max) = 711 nm (epsilon = 140 M-1 cm(-1)), and a phenolate to Cu(II) ligand-to-metal charge transfer (LMCT) band at lambda(max) = 429 nm (epsilon = 950). LMCT excitation of Cu-II(dps)(2) leads to the reduction of Cu(II) to Cu(I). Copper(II) disappears with phi = 2.8 x 10(-3) at lambda(irr) = 436 nm. (C) 2003 Elsevier B.V. All rights reserved.