Molecular structures of carbonyl-linked bis(dioxolene) complexes: Can a carbonyl group act as an effective ferromagnetic coupler?

Molecular structures of two bis(Zn(II)dioxolene) complexes are described: ( Tp(Cum,Me)Zn)(2)1-H-2 (C106H123,50B2N12O10Zn2), tetragonal, P4/ncc, a = 25. 1810(2) Angstrom, b = 25.1810(2) Angstrom, c = 34.7744(2) Angstrom, alpha = 90 degrees, beta = 90 degrees, gamma = 90 degrees, Z = 8; (Tp(Cum,Me)Zn)(2 )1-H (C101H120B2N12O6Zn2), triclinic, P (1) over bar, a = 13.6624(2) Angstr om, b = 13.80920(10) Angstrom, c = 26.62340(10) Angstrom, alpha = 96.6910(1 0)degrees, beta = 91.8560(10)degrees, gamma = 109.0190(10)degrees, Z = 2. O ne of the complexes, (Tp(Cum,Me)Zn)(2)1-H-2, has two protonated catecholate ligands, while the other complex, (Tp(Cum,Me)Zn)(2)1-H-2 has one protonate d catecholate and one semiquinone ligand. When reacted with PbO2, a labile S = 1, bis(Zn-II-semiquinone) complex is formed in which the two semiquinon es are attached to a common carbonyl group.