Reaction of GeCl4 with some phosphorus and arsenic donor ligands; crystal structures of the germanium(II) complex [(Bu3PCl)-P-n][GeCl3] and the germanium(IV) complex GeCl4(AsMe3)(2), the first reported example of a tertiary arsine complex of Ge-IV

The tertiary phosphines PR3 {R-3 = Me-3, Et-3, Pr-3(n), Bu-3(n), Bu-3(t), ( C6H11)(3), [2,6-(CH3O)(2)C6H3](3), [2,4,6-(CH3O)(3)C6H2](3), (C6H5CH2)(3), (Me2N)(3), (Et2N)(3), ((Pr2N)-N-n)(3), Ph2Et or Ph-3} and tertiary arsines AsR3 (R = Ph or Me) have been treated with germanium tetrachloride in both a 1 : 1 and 2: 1 stoichiometric ratio in diethyl ether solution. In the ter tiary phosphine reactions a redox reaction occurs to produce the ionic germ anium(II) complexes [R3PCl][GeCl3] in near to quantitative yield, the chlor ophosphinium cation being identified by P-31-{H} NMR spectroscopy. No evide nce for the previously reported molecular germanium(IV) adducts GeCl4(PR3)( 2) was observed, apart from the possible assignments of minor peaks in the P-31-{H} NMR spectrum for some of the products. The crystal structure of [( Bu3PCl)-P-n][GeCl3] revealed no interaction between the cation and anion, i n direct contrast to the only other reported complex of this stoichiometry, [(Pr3PBr)-P-i][GeBr3]. No reaction was observed between PPh3 and GeCl4. Th e reaction of AsMe3 with GeCl4 in both a 1 : 1 and 2: 1 stoichiometric rati o produced the molecular trans-octahedral germanium(IV) complex, GeCl4(AsMe 3)(2), the first crystallographically characterised germanium(IV) tertiary arsine complex [d(Ge-As) = 2.472(1) Angstrom]. No reaction occurred between GeCl4 and AsPh3.