Reactivity of co-ordinated ligands. Part XIX. (π-Cyclopentadienyl)rhodium complexes of some cyclic monoterpenoids

Abstract

(π-Cyclopentadienyl)rhodium complexes of limonene, α-phellandrene, and carvone have been prepared by the reaction of (C₂H₄)Rh₂Cl₂ and the appropriate monoterpenoid followed by treatment with TlC₅H₅. The complexes undergo protonation in CF₃CO₂H to yield monocationic π-allylic species. The mechanism of proton addition is discussed and compared with that previously proposed for C₆H₈Rh(π-C₅H₅).