Niobium and tantalum tris(methimazolyl)borate complexes [M(=NC 6 H 3 i Pr 2 -2,6)Cl 2 {HB(mt) 3 }] (M = Nb, Ta; mt = Methimazolyl)

Abstract

The first early transition metal tris(methimazolyl)borate complexes [M(=NR)Cl2{HB(mt)3}] (M = Nb, Ta; R = C6H 3iPr2-2,6; mt = methimazolyl) have been obtained from the reactions of [Nb(=NR)Cl3(DME)] or [Ta(=NR)Cl 3(THF)2] (DME = dimethyl ether; THF = tetrahydrofuran) with Na[HB(mt)3] and structurally characterized, illustrating that the HB(mt)3 ligand can indeed be compatible with "hard" metals in high oxidation states.