Photochemical reactions of M(CO)6 (M = Cr, Mo, W) with Ph2P(S)P(S)Ph2

New complexes {M(CO)4[Ph2P(S)P(S)Ph2]} (M = Cr, Mo and W), (1a)–(3a), [(1a), M = Cr; (2a), M = Mo; (3a), M = W] and {M2(CO)10[μ-Ph2P(S)P(S)Ph2]} (M = Cr, Mo, W), [(1b)–(3b) [(1b), M = Cr; (2b), M = Mo; (3b), M = W]] have been prepared by the photochemical reaction of M(CO)6 with Ph2P(S)P(S)Ph2 and characterized by elemental analyses, f.t.-i.r. and 31P-(1H)-n.m.r. spectroscopy and by FAB-mass spectrometry. The spectra suggest cis-chelate bidentate coordination of the ligand in {M(CO)4[Ph2P(S)P(S)Ph2]} and cis-bridging bidentate coordination of the ligand between two metals in (M = Cr, Mo and W).