Co-ordinatively unsaturated acetylene complexes of molybdenum and tungsten; the influence of a second metal on the cyclisation of co-ordinated acetylenes. X-Ray crystal structure of [W(η5-C5H5){C(CF3)= C(CF3)C(CF3)= C(CF3)}(CO)2CO(Co)2]

Abstract

Bis(hexafluorobut-2-yne) complexes [M(η⁵-C₅H₅)Cl(CF₃CCCF₃)₂](M = Mo, W) react with [Co₂(CO)₈] to give acetylene-bridged derivatives [M(η⁵-C₅H₅)CO(µCF₃CCCF₃)₂Co(CO)₂] which react further to give the metallacyclopentadiene complexes [[graphic omitted](CF₃)}(CO)₂Co(CO)₂] which, for M = W, has been structurally characterised by X-ray diffraction methods.