SYNTHESIS AND CHARACTERIZATION OF NOVEL HETEROBIMETALLIC HALIDE ISOPROPOXIDES BASED ON M(2)(OPRI)(9)(-) (M=SN, ZR OR TI) ANIONS - CRYSTAL AND MOLECULAR-STRUCTURES OF [CDI(SN-2(OPRI)(9))] AND [(SNI[ZR-2(OPRI)(9)])(2)]

New heterobimetallic halide isopropoxides based on the interaction of M(2)(OPri)(9)(-) (M - Sn-IV, Zr-IV or Ti-IV) units with Cd-II, Sn-II a nd Pb-II have been prepared. These complexes have been characterised b y multinuclear solution and solid-state cross polarisation magic angle spinning (CP MAS) NMR spectroscopy, elemental analyses and cryoscopy. Single-crystal X-ray diffraction studies have been performed for [CdI {Sn-2(OPri)(9)}] 1 and [{SnI[Zr-2(OPri)(9)]}] 2. Compound 1 consists o f a face-sharing bioctahedral Sn-2(OPri)(9)(-) unit which interacts wi th the central metal atom; cadmium, using two mu- and two terminal OPr i groups. The cadmium atom is within a distorted trigonal bipyramid of oxygen and iodine atoms. The Cd-113 chemical shifts in the solution a nd solid-state CP MAS NMR spectra of 1 are consistent with the retenti on of its heterometallic nature in solution.:In contrast to the monome ric form of 1, compound 2 exists as an iodo-bridged dimer in the solid state. Cryoscopic measurements for 2 indicate a monomer-dimer equilib rium (eta = 1.6) in solution which has been confirmed by variable-temp erature Sn-119 NMR studies. In the solid state the ligating mode of th e Zr-2(OPri)(9)(-) unit in 2 is different from isostructural Sn-2(OPri )(9)(-) and it binds to tin via only three OPri groups, the fourth M-O Pri interaction being hindered by the stereochemically active lone pai r of electrons present at Sn-II. The central SnI2O6 core in 2 can be v iewed as two SnI2O3 octahedra fused along a common axial-equatorial ed ge where one of the axial co-ordination Sites in each is occupied by t he non-bonding electron pair of Sn-II.