Structural Characteristics of S-Bridged Trinuclear Complexes [{Pd(terpy)}_2{Pd(aet)_2}]~(4+)(terpy = 2,2':6',2''-Terpyridine, aet=2-Aminoethanethiolate): Effects of Counter Anions and Solvent on Intra- and Intermolecular Stacking Arrangements

摘要

S-bridged trinuclear Pd(II) complexes, [{Pd(terpy)}_2{Pd(aet)_2}] X_4·nSolv (terpy = 2,2':6',2''-terpyridine, aet = 2-aminoethanethiolate; X = PF_6~-, n = 2, Solv = CH_3CN (1); X = BF_4~-, n = 0.5, Solv = H_2O (2); X = BF_4~-, n = 0 (3); 2X = SiF_6~(-2), n = 6, Solv =H_2O (4)), were obtained by the reactions of [Pd(aet)_2] (aet = 2-aminoethanethiolate) with [Pd(NO_3)(terpy)]~+ (terpy = 2,2':6',2''-terpyridine) using some kinds of counter anions and solvents. The molecules of 1-4, whose structures were determined by X-ray crystallography, contain two {Pd(terpy)} moieties bridged by one [Pd(aet)_2] unit. Although the molecular structures of these complexes are similar to each other, they have significantly different intermolecular structures from each other. While 1 and 2 take monomeric structures, 3 and 4 exist as polymeric forms. These structural features also reflect their diffuse reflection spectra.