Versatile Reaction Pathways of 1,1,3,3,3-Pentafluoropropene at Rh(I) Complexes [Rh(E)(PEt3)3] (E=H,GePh3, Si(OEt)3, F,Cl): C-F versus C-H Bond Activation Steps

The reaction of the rhodium(I) complexes Rh(E)(PEt₃)₃] (E=GePh₃ ( 1 ), H ( 6 ), F ( 7 )) with 1,1,3,3,3-pentafluoropropene afforded the defluorinative germylation products Z/E-2-(triphenylgermyl)-1,3,3,3-tetrafluoropropene and the fluorido complex Rh(F)(CF₃CHCF₂)(PEt₃)₂] ( 2 ) together with the fluorophosphorane E-(CF₃)CH=CF(PFEt₃). For Rh(Si(OEt)₃)(PEt₃)₃] ( 4 ) the coordination of the fluoroolefin was found to give Rh{Si(OEt)₃}(CF₃CHCF₂)(PEt₃)₂] ( 5 ). Two equivalents of complex 2 reacted further by C−F bond oxidative addition to yield Rh(CF=CHCF₃)(PEt₃)₂(μ-F)₃Rh(CF₃CHCF₂)(PEt₃)] ( 9 ). The role of the fluorido ligand on the reactivity of complex 2 was assessed by comparison with the analogous chlorido complex. The use of complexes 1 , 4 and 6 as catalysts for the derivatization of 1,1,3,3,3-pentafluoropropene provided products, which were generated by hydrodefluorination, hydrometallation and germylation reactions.