Chemistry of polynuclear metal complexes with bridging carbene or carbyne ligands. Part 83. Molybdenum and tungsten complexes containing the alkylidyne group C{η6-C6H4(OMe-2)Cr(CO)3}

Abstract

The alkylidyne-metal complexes [CrM{µ-σ:η⁶-CC₆H₄(OMe-2)}(O₂CCF₃)(CO)₅L₂][M = Mo or W, L₂= tmen (Me₂NCH₂CH₂NMe₂) or bipy (2,2′-bipyridine)] and [CrM{µ-σ:η⁶-CC₆H₄(OMe-2)}(CO)₅L]{M = Mo, L =η-C₅H₅ or HB(pz)₃[hydrotris(pyrazol-1-yl)borate]; M = W, L =η-C₅H₅} have been prepared. In these species the alkylidyne ligand attached to Mo or W is η⁶-co-ordinated to a Cr(CO)₃ group. Several reactions of the complexes [CrM{µ-σ:η⁶-CC₆H₄(OMe-2)}(CO)₅(η-C₅H₅)] with low-valent metal compounds have been studied. These have led to the isolation of various heteronuclear metal cluster compounds with bonds between molybdenum or tungsten and platinum, nickel, cobalt, and rhodium. The n.m.r. data for the new products are reported and discussed in relation to the structures proposed.