Oxidative addition reactions of tri(2-methylphenyl)antimony

Bis??-oxo-tri(2-methylphenyl)antimony] (I) was synthesized via oxidation of tri(2-methylphenyl)antimony by hydrogen peroxide in ether. In the presence of 2-hydroxy-5-bromobenzaldoxime or furfural oxime, the reaction between these reactants (in a 1: 1: 1 molar ratio, respectively) yields (??-oxo)bis2-hydroxy-5-bromobenzaldoximato-tri(2-methylphenyl)antimony] (II) or (??-oxo)bisfurfural-oximatotri(2-methylphenyl)antimony] (III). The structures of compounds I?CIII was determined by X-ray diffraction. In the centrosymmetric dimeric complex I, the Sb atom has a distorted trigonal-bipyramidal coordination with oxygen atoms in equatorial and axial positions. In II and III, the axial positions are occupied by the bridge oxygen atom and the oxygen atom of the oxime ligand. Bond length values are as follows: Sb-C 2.137(3)?C2.183(3), 2.116(7)?C2.131(7), and 2.105(5)?C2.126(6)?; Sb-O 1.934(2), 2.077(2), 1.973(4)?C2.151(4), and 1.9706(3)?C2.112(6) ? for I, II, and III, respectively. Intramolecular contacts Sb...N (2.953(8), 3.002(9), and 2.951(8) II and III.