Ferrocene derivatives. 23. Isocyanoferrocene and isothiocyanatoferrocene

Aminoferrocene has been converted into formamidoferrocene, which exists in solution as an equilibrium mixture of two rotational isomers, a monomeric cis form and a dimeric (or oligomeric) transform. Variable-temperature {sup 1}H and {sup 13}C({sup 1}H) NMR spectra have been used to measure {Delta}G{double dagger} for the hindered internal rotation about the C-N bond. Dehydration of formamidoferrocene yields isocyanoferrocene, which has been characterized by complex formation with iron and molybdenum carbonyls. A high-yield conversion of aminoferrocene into isothiocyanatoferrocene is described.