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.