Ethyldiphenylphosphin und 1.2-Bis [bis(β-diphenylpho8phinoethyl)pho8phino] ethan: Derivate des Hexacarbonyl]iydridovanadium(+I) und Hexacarbonylvanadat(—I) / Ethyldiphenylphosphine and l,2-Bis[bis(β-diphenylphosphinoethyl)phosphino]ethane: Derivatives of Hexacarbonylhydridovanadium(+I) and Hexacarbonylvanadate(—I)

Abstract

The coordination properties of Ph2PEt (pi) and (Ph2PCH2CH2)2PCH2CH2P(CH2CH2PPh2)2 (P2P4) towards HV(CO)6 and [V(CO)6]- are compared. Preparation and spectral properties (IR, 1H, 31P and 51V NMR) are described for the complexes HV(CO)4(p1)2, [Et4N][V(CO)6-n(p1)n] (n = 1, 2), HY(CO)mP2P4 (m = 1-5) and [Et4N][V(CO) mP2P4] (M = 1-3). The anionic species are obtained by photo-induced CO exchange, the hydrido complexes by treatment of the anionic complexes with t-BUCl/H2O or - more conveniently - by ion exchange on silica gel (m - 1-3) and subsequent UY irradiation (m = 4, 5). Complexes containing four CO groups are cis-configurated, the p1 species being extremely labile. Trisubstitution yields an isomeric mixture of mer- and fac-[V(CO)3p2p4]-. A consistent explanation of the 1H pattern in the hydride region is possible on the basis of a facecapped octahedral structure with a restricted dynamic behaviour. The positions of the CO ligands in HV(CO)3p2p4 and HV(CO)2P2P4 are facial and trans, respectively. Only chelate five-ring structures are formed.