Reaktivität von Monophosphan-Platin(0)-Verbindungen gegenüber Schwefeldioxid

Reactivity of Monophosphine Platinum(0) Complexes with SO₂ . The addition reaction of (PPh₃)Pt(ViSi) (ViSi = {η²-H₂C?CHSiMe₂}₂O) ( 1 ) with SO₂ gives within 30 min the red SO₂ complex (PPh₃)Pt(η²-H₂C?CHSiMe₂- OSiMe₂CH?CH₂)(SO₂) ( 2 ). A reaction time of 24 h with SO₂ leads to the elimination of the ViSi ligand, and the unstable monomeric intermediate (PPh₃)Pt(SO₂) cyclo- trimerizes to the stable cluster Pt(PPh₃)(SO₂)]₃ ( 3 ). 3 is also obtained within 30 min by the reaction of (PPh₃)Pt(C₂H₄)₂ ( 4 ) with SO₂. The crystal structure of 3 has been determined; space group P2₁/n, Z = 4, a = 1 606.1(3), b = 1 019.3(1), c = 3 624.6(5) pm, β = 93.67°, R/R_w = 0.102/0.121.