Niobium(III) complexes containing acetylene, isocyanide, phosphine or phosphite ligands

Abstract

The reduction of THF solutions of (η-C5H5)2 NbCl2 with Na/Hg in the presence of various phosphines, phosphites, acetylenes or isocyanides gives complexes of the type (η-C5H5)2 NbClL, where L  PMe2 Ph, P(OMe)3, PhCCPh, PhCCH, HCCH, CNPh, or CNCy. A complex is also formed in solution from PEt3 but cannot be isolated as a solid. For L  P(OPh)3 no stable compound can be obtained. The IR, 1H and 13C NMR spectra of the complexes are described.