Vanadium-Induced Nucleophilic IPSO Substitutions in a Coordinated Tetrachlorosemiquinone Ring: Formation of the Chloranilate Anion as a Bridging Ligand

In basic media, the coordinated semiquinone radical in the spincoupled [(bipy)ClVIVO(TCSQ)] 1 (HTCSQ ) tetrachlorosemiquinone) undergoes nucleophilic ipso substitution (OH- for Cl-) to generate the chloranilate anion (CA2-) that bridges the vanadium(IV) centers, forming a binuclear compound [(bipy)ClVIVO(CA)OVIVCl(bipy)] 2

Bi- and trinuclear copper(II) complexes of a sterically constrained phenol-based tetradentate ligand: syntheses, structures, and magnetic studies

Cu(II) complexes of a sterically constrained phenol-based tetradentate N2O2 ligand 1,4-bis(2-hydroxy-3,5-dimethylbenzyl)piperazine (H2L) are reported. The assocd. anions of the Cu(II) ion precursors have profound influence on the stoichiometry of the products. Thus, with perchlorate ion, the product is binuclear [Cu2L2] (1), while with coordinating anions viz. Cl- and N3-, [Cu3L2Cl2(H2O)]×0.5H2L (2) and [Cu3L2(N3)2(MeOH)]×4H2O (3) have triangulo trinuclear compn. The syntheses, x-ray structures, and spectroscopic and magnetic properties of these complexes are described..