Organometallic complexes with electronic bridges. 2. Phenylene-bridged organometallic complexes of iron and manganese

(q5-C5Hs)Fe(CO),, ),, or Mn(CO)5) is described. These species are best prepared in two steps by metathesis of the organometallic anion, NaML,, with the appropriate aroyl chloride to give acyl intermediates. These complexes were isolated and then thermally decarbonylated (in refluxing butyl ether and THF for the Fe and Mn complexes, respectively) to give the desired products in 40-90% overall yield. Their perfluoro analogues, 1,4-C6F4Fp', (where Fp' = (q5-C5H5)Fe(C0), or (q5-C5H4Me)Fe(CO),), are prepared in 30430% yield by the metathesis of 1,4-C6F4Liz with Fp'I. These new materials have been fully characterized by conventional spectroscopic techniques and are shown to contain metal-arene u bonds. Evidence is provided for partial dimetalloquinone character in the bonding of the para-substituted species. The reactions of the title compounds with phosphines (to give carbonyl substitution products) and with halogens (to give metal-aryl bond cleavage) are also reported.