Geoffrey Wilkinson

Geoffrey Wilkinson shared the 1973 Nobel Prize in Chemistry with Ernst Otto Fischer for their independent pioneering work on the chemistry of organometallic sandwich compounds. Wilkinson determined that ferrocene, a molecule containing an iron atom sandwiched between two cyclopentadienyl rings, had this distinctive layered structure.

Wilkinson's catalyst is chlorotris(triphenylphosphine)rhodium(I), a square-planar rhodium complex with the formula RhCl(PPh₃)₃ that serves as a highly selective catalyst for the hydrogenation of alkenes. Wilkinson discovered it in the mid-1960s, and it became one of the most widely studied and commercially important homogeneous hydrogenation catalysts.

Wilkinson proposed in 1952 that ferrocene consisted of an iron atom sandwiched between two parallel cyclopentadienyl rings, a structure that explained its unusual stability and magnetic properties. This proposal, made independently of similar conclusions by Fischer's group in Munich, overturned the initial assumption that ferrocene had a conventional sigma-bonded structure.

Wilkinson carried out his Nobel Prize-winning organometallic chemistry research at Imperial College London, where he was appointed to the chair of inorganic chemistry in 1956. He remained at Imperial College for the rest of his career and built one of the world's leading inorganic chemistry research groups.