OXYGEN-BRIDGED HEXA(ORGANO)DI-ANTIMONY COMPOUNDS - HYDROLYSIS BY TRACES OF MOISTURE AND CRYSTAL-STRUCTURES OF [SBR3BR](2)O, WHERE R = P-TOLYL OR O-TOLYL

H-1 and C-13 NMR spectroscopy of four compounds of the type [SbR3X](2) O, where X = Br and R = Ph, p-tolyl and o-tolyl or X = Cl and R = Me, have been interpreted as showing that unless stringent precautions are taken to exclude moisture there is cleavage of the oxygen bridge to g ive solutions which contain both the hydroxo species, SbR3(OH)X, and t he original bridged compound. This is in agreement with earlier result s from IR spectra of compounds of this type in the presence of water. Rigorous exclusion of moisture leads to NMR spectra of only the unhydr olysed compound and this is the only product isolated when NMR solutio ns showing the presence of both compounds are crystallised. On the oth er hand, a stable hydroxobromide, Sb(mesityl)(3)Br(OH), has been isola ted from hydrolysis of Sb(mesityl)(3)Br-2. Crystal structures are repo rted for the o- and p-tolyl isomers of [Sb(tolyl)(3)Br](2)O; the latte r has crystallographically imposed 3 symmetry with a linear Sb-O-Sb br idge but the two independent molecules of the o-tolyl derivative have bridge angles of 161.0(2) and 171.5(2)degrees, respectively. (C) 1997 Elsevier Science S.A.