A NOVEL SYNTHESIS OF ORGANOIMIDO COMPLEX BY TRANSAMINATION REACTION - X-RAY CRYSTAL-STRUCTURE OF BIS-(ISOPROPYLIMIDO) COMPLEX OF TUNGSTEN(VI), [W(MU-NPRI)(NPRI)(NHPRI)2]2

Abstract

The bis(isopropylimido) complex [W(mu-NPri)(NPri) (NHPri)(2)](2) was synthesized by reacting W-2(NBu(i))(2)(NHBu(i))(2) with excess (PrNH2)-N-i. The complex, characterized by X-ray crystallography, is a dimer of distorted trigonal bipyramids sharing an edge defined by the unsymmetrical bridging imido ligands. Exchange between the bridging and the terminal imido ligands were observed on the NMR timescale, Delta G double dagger = 14.5+/-1.0 kcal mol(-1). An equilibration process is proposed to account for the fluxional behaviour.