Behavior Characteristic of (η5-Cyclopentadienyl)(1,2-di-2-pyridyl-1,2-ethylenedithiolato)cobalt(III) and Its Diselenolato Analog. Elimination of 2S or 2Se and Exchange of S and Se

(η5-Cyclopentadienyl)(1,2-di-2-pyridyl-1,2-ethylendithiolato)cobalt(III) (1) and its selenium analog (2) show interesting reactivities at the S and Se moiety. A characteristic peak in MS of 1and 2measured using a direct inlet system under heating is found at m/z=304 assigned to ((M-2S)+or (M-2Se)+). The reflux of 2in toluene with S8causes the exchange of Se by S in the complex.