SPECTROSCOPIC AND ELECTROCHEMICAL OBSERVATION OF BOTH 17-ELECTRON AND19-ELECTRON STATES OF AN INORGANOMETALLIC TRANSITION-METAL COMPLEX - [FE-III(ETA(5)-C(5)ME(5))(S(2)CNME(2))(2)]

The blue 19e complex [Fe-III(C(5)Me(5))(eta(2)-S(2)CNMe(2))2] 1, gener ated by addition of NaS(2)CNMe(2) to the 17e complex [Fe-III(C(5)Me(5) )(eta(2)-S(2)CNMe(2))(MeCN)]PF6 in MeCN at -45 degrees C or by monoele ctronic reduction of the 18e cation 1(+) using the 19e complex [Fe-I(C 5H5)(C(6)Me(6))] in THF at -80 degrees C gives the purple 17e form 5)M e(5))(eta(2)-S(2)CNMe(2))-{eta(1)-SC(S)NMe(2)}] 2 in solution and in t he solid state; both the 17e and 19e forms are characterized by their specific ESR and Mossbauer spectra and by cyclic voltammetry.