Journal of Supercritical Fluids, Vol.131, 117-123, 2018
Phosphonium salts derived from alpha-ferrocenylvinyl cation in situ generated in sc-CO2 from ethynylferrocene by Nafion film
A protonation of ethynylferrocene by nafion in sc-CO2 in the presence of triphenylphosphine (PPh3) or 1,2-bis (diphenylphosphino)ethane (DPPE) leads to a formation of novel (1-ferrocenylvinyl)phosphonium or ferrocenyl substituted bisphosphonium salt isolated as tetrafluoroborates 3 and 4, respectively. Ferrocenyl substituted bisphosphonium tetrafluoroborate 4 undergoes the hydrolytic cleavage of the P+-C(Fc) bond in the presence of Al2O3 at 25 degrees C to form ferrocenyl substituted phosphinyl phosphonium tetrafluoroborate 5. Complexes 3-5 were completely characterized by NMR spectra and their molecular structures elucidated by X-ray studies.
Keywords:Supercritical carbon dioxide;Nafion film;Alkynes protonation;Carbenium ions;Phosphonium ions;Phosphinyl phosphonium ions