Synthesis and crystal structure of oxalato-bridged dicopper(II) complex with reduced imino nitroxide radicals

A new oxalato-bridged dicopper(II) complex [Cu-2(mu -C2O4)(Him2-py)(2)(NO3) (2)]CH3OH has been synthesized and its crystal structure determined by X-ra y diffraction methods. The imino nitroxide 2-(2'-pyridyl)-4,4,5,5-tetrameth yl-4,5-dihydro-1H-imidazolyl-1-oxyl(im2-py) is reduced in the reaction to y ield 2-(2'-pyridyl)-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazolyl-1-hydroxy (Him2-py). The structure consists of centrosymmetric [Cu-2(mu -C2O4)(Him2-p y)(2)(NO3)(2)] and one solvent methanol molecule. Each Cu(II) ion is in a d istorted tetragonal pyramid environment: two nitrogen atoms from Him2-py, t wo oxygen atoms from the oxalate ion in the basal plane and one oxygen atom from the nitrato group in the axial position. (C) 2001 Elsevier Science B. V. All rights reserved.