The reaction of the differently substituted cyclopentadienyl complexes LzM,(CO), with sulfur is investigated with respect to the ligand L (etmcp = ethyltetramethylcyclopentadienyl, tbcp = tbutylcyclopentadienyl, ipcp = isopropylcyclopentadienyl) and the metal M (Cr, MO, W). For M = Cr the only isolated product is etmcp,Cr,S,. For M = MO three isomers A, D, E of composition LzMo,S, (L = ipcp, etmcp) are formed whereas only two isomers (A, D) exist for L = tbcp. Only two isomers (D, E) of composition LzWzS, are formed in the system LzWz(CO), /S,, a further product is LzWz(CO)zS, for L = etmcp. Structural characterisation of all compounds was achieved by IR, 'H, and 95Mo NMR spectroscopy, whereas the structures of ryn-etmcp,M&-S),S, (M = MO, W) were determined by X-ray crystallography, the result of which allows the correction of a previous structure assignment. It is further shown that a thermal equilibrium exists between L,Mo,(~,gZ-S,X~-S), (A) and syn-L,Mo& S&S, (D) which depends strongly on the ligands.