Reactions of [MCl2(PhCN)2] (M = Pd or Pt) and K2[PtCl4] with S,S-dimethyl-N-heteroaromatic sulphimides Me2SNR (R = 2-pyridyl, 4-methyl-2-pyridyl, 2-pyrimidinyl, 4-methyl-2-pyrimidinyl, or 2-pyrazinyl) give 1:1 adducts trans-[M2Cl2(µ-Cl)2(Me2SNR) 2] (1) in which the sulphimide appears to co-ordinate through the ylide nitrogen according to 1H n.m.r. studies. Reaction of [MCl2(PhCN)2] with Me2SNPh gives a bis(sulphimide) complex trans- [MCl2(Me2NSPh)2] (2) when M = Pd but when M = Pt a phenylnitrene derivative cis-[PtCl2(Me2SNPh) (NPh)] (3) is obtained. Reactions of complexes (1) with phosphines L = PEt3, PMe2Ph, PMePh2, or PPh3, give 1:1 adducts [MCl2L(Me2SNR)] [M = Pd; R = 2-pyridyl, L = PEt3, PMe2Ph, PMePh2, or PPh3, (4a)-(4d); M = Pt, R = 2-pyridyl, L = PEt3 (4e); M = Pd, R = 2-pyrimidinyl, L = PPh3 (4f)]. An X-ray analysis of cis- [PdCl2(PPh3) (Me2SNC4H3N2)]·CH 2Cl2 (4f) revealed that the pyrimidine rather than the sulphimide N atom is the point of attachment of the sulphimide ligand to Pd. Conformational energy calculations suggest that electronic rather than steric factors determine which N atom acts as donor to Pd. The crystals are monoclinic, space group P21/n, with a = 17.307(6), b = 9.182(1), c = 17.960(2) Å, ß = 97.15(2)°, R = 0.024 for 1 999 independent reflections with I > 3s(I). N.m.r. studies suggest a trans structure for complex (4e) with sulphimide co-ordination via the pyridyl nitrogen. The isomerism and fluxional behaviour of (4c) and (4d) was studied by variable-temperature n.m.r. spectroscopy. © Copyright 1989 by the Royal Society of Chemistry.
|Number of pages||8|
|Journal||Journal of the Chemical Society, Dalton Transactions|
|Publication status||Published - 1989|