Synthesis and crystal structure of bis{di-µ-hydroxobis[fac-tribromoaquotin(IV]} heptahydrate

A product isolated from a reaction mixture of Br-2 and Ph-3 Sn(CH2)(13)CH3 (3:1 mole ratio) in CHCl3 solution in air was bis{di-mu-hydroxobis[fac-tribromoaquotin(VI)]} heptahydrate, 2[Br-3 (H2O)Sn(mu-OH)(2) Sn(O2H)Br-3] center dot 7H(2)O, 2[fac-(1: X = Br)]. 7H(2)O. Previous reports had indicated that the tin complexes, [fac-(1: X = Cl or Br)], had been obtained in various solvated forms from hydrolysis or oxidation/hydrolysis of appropriate tin(IV) or tin(II) halides. The crystal structure determination, reported here, provides an improved refinement of the core, i.e., [fac-(1: X = Br)], of 2[fac-(1: X = Br)] center dot 7H(2)O compared to previous attempts. The solid state structure consists of a central rhomboidal planar Sn2O2 ring. The tin centres have distorted octahedral geometries, with each Br ligand trans to an 0 atom. The Br ligands, trans to the aqua ligands, form longer bonds to tin at 2.5556(7) and 2.5544(6) angstrom, than those trans to the bridging OH ligands, between 2.5021(7) and 2.5127(7) angstrom. The Br, OH and H2O ligands as well as the solvate water molecules are all involved in an extensive hydrogen bonding system in 2[fac-(1: X = Br)] center dot 7H(2)O. (c) 2005 Elsevier B.V. All rights reserved.