Oxidation of tetraaryldistibanes:: syntheses and crystal structures of diarylantimony oxides and peroxides, (R2Sb)2O, (R2Sb)4O6 and (R2SbO)4(O2)2 (R = Ph, o-Tol, p-Tol)

Tetraaryldistibanes, (R2Sb)(2) (R = Ph, o-Tol, p-Tol) are synthesized by the reactions of R2SbNa with BrCH2CH2Br in liquid ammonia. They react with air oxygen to form (R2Sb)(4)O-6 and (R2Sb)(4)O-6. The reactions of (R2Sb)(4)O-6 with H2O2 give peroxides, (R2SbO)(4)(O-2)(2), Single-crystal X-ray structure analyses reveal that the conformations of the (R2Sb)(2)O-6 molecules are close to syn-syn (R = Ph) or to syn-anti (R = o-Tol, p-Tol). (Ph2SbO)(4)(O-2)(2) is an antimony-oxygen cluster with mu(4)-peroxo ligands. (C) 2002 Elsevier Science B.V. All rights reserved.