New ion-pair nickel(III) complexes containing [Ni(‘S2’)2] (‘S2’2−=1,2-benzenedithiolate) fragments: synthesis, crystal structure and properties
摘要:
Two new ion-pair complexes [1-(4'-fluorobenzyl)pyridinium][Ni(bdt)(2)] (1) and [1-(4'-bromobenzyl)pyridinium][Ni(bdt)(2)] (2), in which bdt(2-) = 1,2-benzenedithiolate ('S-2(,2-)), have been prepared and characterized. X-ray structural analyses showed that 1 and 2 are isostructural, and the anions are centrosymmetric. The 2 non-equiv. anions form different uniform-spaced stacking pattern in I and 2. The magnetic measurements of 1 and 2 indicate ferromagnetic behavior in the antiferromagnetic exchange system, which may arise from spin canting. Cyclovoltammetry revealed two quasi-reversible one-electron steps for I and 2, which are attributed to Ni(IV/III) and Ni(III/II) redox couples. (C) 2002 Elsevier Science Ltd. All rights reserved.