Hydrolysis and condensation of chlorophosphine and alkyl phosphite ligands on platinum and palladium. 31P and 195Pt nuclear magnetic resonance studies and the crystal and molecular structures of [Pt2Cl4{μ-(EtO)2POP(OEt)2}2] and [Cl2Pt{μ-(P(OEt)2O)2P(O)}PtCl(PEt3)2]

Hydrolysis of cis-[PtCl2-{P(OEt)2Cl}2] results in condensation of the phosphite to form [Pt2Cl4{μ-(EtO)2POP(OEt)2}2], which crystallizes in the monoclinic space group P21/n, with a = 13.814(7), b = 11.429(4), c = 10.726(5) Å, β = 106.30(5)°. Reactions of P(OEt)2Cl or (EtO)2POP(OEt)2 with [Pt2Cl4(PEt3)2] also yield very easily hydrolyzed products but in these cases an even more complex condensation occurs to yield [Cl2Pt{(μ-(P(OEt)2O)2P(O)}PtCl(PEt3)2], which crystallizes in the monoclinic space group P21/c, a = 17.547(8), b = 19.775(6), c = 11.268(3) Å, β = 106.42(3)°. Complete X-ray diffraction studies are reported for both crystals, confirming the presence of double (EtO)2POP(OEt)2 bridges in [Pt2Cl4{(μ-(EtO)2POP(OEt)2}2] and a novel triphosphite bridge in [Cl2Pt{μ-(P(OEt)2O)2P(O)}PtCl(PEt3)2]. Detailed analyses and computer simulation of the 31P{1H} and 195Pt{1H} nmr spectra of these complexes are also described, together with studies of the related compounds, [Pt2Me4{μ-(EtO)2POP(OEt)2}2] and [Cl2(Et3P)Pt{μ-(EtO)2POP(OEt)2}PtCl2(PEt3)]. In conjunction with previous studies of [Pt2Cl2(dppm)2] and related complexes, these spectra provide examples of several types of AA′XX′ spin systems and the analysis of these systems is discussed in detail.