Direct one step preparation and 13C-NMR spectroscopic characterization of alpha-ferrocenyl carbocations derived from ferrocene and carbonyl compounds in trifluoroacetic acid medium1a

G.K. Surya Prakash, Herwig A. Buchholz, Julian F.S. Vaughan, Qi Wang, George. A. Olah
1999 Journal of the Brazilian Chemical Society  
A reação de aldeídos e cetonas com ferroceno, na presença de ácido trifluoroacético, gera uma série de α-ferrocenoalquil carbocátions estáveis por longo tempo que foram caracterizados por espectroscopia de Ressonância Magnética Nuclear de 13 C. De forma inesperada, quando esta reação foi realizada usando tetrafenilciclopentadienona, o correspondente dihidro derivado 3 foi isolado com muito bom rendimento. A formação deste composto pode requerer ferroceno atuando como agente redutor. Reaction of
more » ... edutor. Reaction of aldehydes and ketones with ferrocene, in the presence of trifluoroacetic acid, afforded a series of stable long lived α-ferrocenylalkyl carbocations which were characterized by 13 C-NMR spectroscopy. When this reaction was attempted using tetraphenylcyclopentadienone, quite unexpectedly the corresponding dihydro derivative 3 was isolated, in very good yield. Formation of this compound may require ferrocene acting as a reducing agent.
doi:10.1590/s0103-50531999000400010 fatcat:ewfaxlbmbnd3pef63eymhewuoa