Preparation and utilisation of organometallic ylids containing the tricarbonyliron unit

Abstract

The reaction of tertiary phosphines, PR₃, with six- and seven-membered ring dienyl complexes of Fe(CO)₃ produces the corresponding phosphoniodiene salts. These salts undergo deprotonation on treatment with either LiBuⁿ or NaH and undergo a subsequent reaction with aldehydes (R′CHO) to yield the appropriate olefinic complexes. With [Fe(CO)₃(η-C₅H₅)][BPh₄], reaction with PR₃ produces simple substitution complexes of the type [Fe(CO)₂(η-C₅H₅)(PR₃)][BPh₃]. Treatment of [Fe(CO)₃(C₈H₇CH₂OH)] with HPF₆ produces a salt of unknown structure which reacts with PPh₃ to produce tricarbonyl(triphenylphosphoniomethylcyclo-octatetraene)iron hexafluorophosphate. Reaction of this salt with LiBuⁿ and HCHO yields tricarbonyl(vinylcyclo-octatetraene)iron.