Carbon–fluorine and –hydrogen bond activation and carbon–carbon bond formation in η5-pentamethylcyclopentadienyl-rhodium and -iridium phosphine complexes; crystal structures of [M(η5-C5Me5)Cl{(C6F5)2PCH2CH2P(C6F5)2}]+BF4–(M = Rh or Ir)
摘要:
The reaction between [{M(eta(5)-C(5)Me(5))Cl(mu-Cl)}(2)] (M = Ph or Ir) and (C6F5)(2)PCH2CH2P(C6F5)(2) (dfppe) in refluxing benzene yielded the cationic species [M{eta(5)-C(5)Me(3)[CH2C6F4P(C6F5)CH2](2)-1,3}Cl](+) in which two C-F and two C-H bonds have been cleaved and two C-C bonds formed; HF is also produced. The complexes [M(eta(5)-C(5)Me(5))Cl(dfppe)](BF4-)-B-+ (M = Ph or Ir), which have not undergone C-F bond activation, were formed by treatment of [{M(eta(5)-C(5)Me(5))Cl(mu-Cl)}(2)] with NH4BF4 and dfppe, and have been structurally characterized by X-ray crystallography. Activation of the C-F bonds in these complexes is induced by thermolysis in refluxing ethanol. The reaction between [{M(eta(5)-C(5)Me(5))Cl(mu-Cl)}(2)] (M = Rh or Ir) and dfppe in refluxing ethanol yielded a mixture of the cations [M(eta(5)-C(5)Me(5))Cl(dfppe)](+), [M{eta(5)-C(5)Me(3)[CH2C6F4P(C6F5)CH2C6F4P(C6F5)CH2](2)-1,3}Cl](+) and, where M = Rh, the singly C-F bond-activated species [Rh{eta(5)-C(5)Me(4)CH(2)C(6)F(4)P(C6F5)CH2-CH2P(C6F5)(2)}Cl](+).