Dithiolate and diselenolate complexes [Pt2(μ-ECH2CH{double bond, long}CHCH2E)(PPh3)4]2+ (E = S, Se): Synthesis, characterisation and mass spectrometric formation of the dichalcogenide species [Pt2(μ-E2)(PPh3)4]2+

Abstract

The reactions of [Pt2(μ-E)2(PPh3)4] (E = S, Se) with cis-1,4-dichlorobut-2-ene (cis-ClCH2CH{double bond, long}CHCH2Cl) give the dichalcogenolate complexes [Pt2(μ-ECH2CH{double bond, long}CHCH2E)(PPh3)4]2+; an X-ray structure determination on the thiolate complex was carried out. The complexes give the expected dications in ESI mass spectra recorded at very low cone voltages, but at moderate cone voltages undergo facile fragmentation via a retro-Diels-Alder reaction and loss of 1,3-butadiene, giving the dichalcogenide species [Pt2(μ-E2)(PPh3)4]2+. Analogous species containing bidentate phosphine or arsine ligands have been previously generated electrochemically, and studied theoretically. © 2008 Elsevier B.V. All rights reserved.