Reactivity of 5-Methylpyridyl-2-Selenolate With Platinoid Metal Precursors: Isolation of Tri and Hexanuclear Complexes via Se-Se and Se-C Bond Cleavage
摘要
A series of palladium (II) and platinum (II) selenolate complexes have been isolated depending upon the nature of the phosphine ligand. The substitution reaction of [PdCl2(PPh3)2] with two equivalents of NaSeC5H3(5-Me)N resulted in the hexanuclear complex [Pd6Br0.87Cl1.13{2-SeC5H3(5-Me)N2}2(PPh3)6] (1a) whereas a chelated compound [Pt{κ-Se, κ-N: SeC5H3(5-Me)N}{SeC5H3(5-Me)N}(PPh3)] (1b) has been obtained in the case of [PtCl2(PPh3)2]. However, chelated phosphine as an ancillary ligand with a similar reaction by using [PtCl2(P∩P)] (P∩P = dppm, dppe) yielded cis-configured monomer [Pt{2-SeC5H3(5-Me)N}2(P∩P)]. The trinuclear complexes [M3(µ-Se)3(dppp)3]2+ [M = Pd (2d), Pt (2e)] were isolated by reactions of [MCl2(dppp)] (M = Pd, Pt) with NaSeC5H3(5-Me)N via facile cleavage of Se-C bond in presence of chlorinated solvents. All the synthesized complexes have been characterized by elemental analyses, 1H, 31P{1H}, 77Se{1H} NMR spectroscopy. The molecular structure of complexes [Pd6Br0.87Cl1.13{2-SeC5H3(5-Me)}2(PPh3)6] (1a) and [Pt{2-SeC5H3(5-Me)N}2(dppm)].C6H5CH3 (2a) were determined by single crystal X-ray diffraction analyses.