Multinuclear NMR studies of diphosphine, diphosphine-dioxide and diarsine complexes of tin(IV) halides. Structures of [SnI4{o-C6H4(AsMe2)(2)}] and [SnI4{o-C6H4(P(O)Ph-2)(2)}]

The complexes [SnX4(L-L)] ( X = Cl or Br. L-L = Me2PCH2CH2PMe2, Ph2PCH2,CH2 PPh2, o-C6H4(PPh2)(2), o-C6H4(ASMe(2))(2), Ph2AsCH2CH2AsPh2) have been isol ated Gonh reaction of SnX4 with the ligand in anhydrous CH2CL2. The complex es have been characterised by analysis, IR and multinuclear NMR (H-1, P-31 and Sn-119)spectroscopy. Rare examples of complexes with SnI4, have been is olated with all the above ligands except Ph2AsCH2CH2AsPh2 and similarly cha racterised. The multinuclear NMR studies reveal reversible ligand dissociat ion in some of the chloro- and bromo-complexes in solution,the extent varyi ng with the neutral ligand involved, but all the iodo-complexes are extensi vely dissociated in solution. Complexes of PMe3, and the diphosphine-dioxid e o-C6H4(Ph2PO)(2) are also described. X-ray structures of [SnI4{o-C6H4(AsM e2)(2)}] and of [SnI4{o-C6H4(Ph2PO)(2)}] and its CH2Cl2 solvate are reporte d. (C) 1999 Elsevier Science S.A. All rights reserved.