ISOLATION AND STRUCTURAL CHARACTERIZATION OF COMPLEXES FORMED IN THE REACTIONS OF [(C5H4(SIME(3)))(2)FE-2(CO)(4)] AND [(1,3-C5H3(SIME(3))(2))(2)FE-2(CO)(4)] WITH ELEMENTAL SULFUR

The reactions of [Cp(2)(S1)Fe(2)(CO)(4)] and [Cp(2)(S2)Fe(2)(CO)(4)] w ith elemental sulfur afforded a tetrairon cluster containing two end-o n type S-2 ligands [Cp(4)(S1)Fe(4)S(6)] (1) and a diiron complex conta ining an end-on type S-2 and a side-on type S-2 ligands [(CP2Fe2S4)-Fe -S2] (2), respectively, where Cp(S1) and Cp(S2) stand for mono- and bi s(trimethylsilyl)cyclopentadienyl ligands, respectively. From these re sults and the previously reported results which were obtained for the reactions of [Cp(2)Fe(2)(CO)(4)] and [CPFe-2(2)(CO)(4)] with elementa l sulfur, it is suggested that [Cp'2Fe2S4] is an intermediate to give tetrairon sulfur clusters, where Cp and Cp' denote pentamethylcyclope ntadienyl and substituted cyclopentadienyl ligands, respectively. X-Ra y crystal structure analysis was carried out for the compounds 1 and 2 . Crystallographic data are as follows: 1: Monoclinic, P2(1)/c, a = 17 .302(6), b = 18.646(3), c = 15.310(4) Angstrom, beta = 120.71(2)degree s, V = 4246(2) Angstrom(3), Z = 4, and R = 0.061 for 5850 reflections with \F-o\ > 3 sigma(F-o; 2: Triclinic, space group <P(1)over bar>, a = 12.602(2), b = 12.891(2), c = 11.401(1) Angstrom, alpha = 114.52(1), beta = 95.45(1), gamma = 88.39(1)degrees, V = 1677.5(4) Angstrom(3), Z = 2, and R = 0.046 for 7343 reflections with \F-o\ > 3 sigma(F-o).