A 2-iridathiophene from reaction between IrCl(CS)(PPh3)2 and Hg(CHdouble bond; length as m-dashCHPh)2

The thiocarbonyl analogue of Vaska’s compound is produced in high yield by first treating IrCl(CO)(PPh3)2 with CS2 and methyl triflate to give [Ir(κ2-C[S]SMe)Cl(CO)(PPh3)2]CF3SO3 (1), secondly, reacting 1 with NaBH4 to give IrHCl(C[S]SMe)(CO)(PPh3)2 (2), and finally heating 2 to induce elimination of both MeSH and CO to produce IrCl(CS)(PPh3)2 (3). When IrCl(CS)(PPh3)2 is treated with Hg(CHdouble bond; length as m-dashCHPh)2 the novel 2-iridathiophene, Ir[SC3H(Ph-3)(CHdouble bond; length as m-dashCHPh-5)]HCl(PPh3)2 (4) is produced. The X-ray crystal structure of the iodo-derivative of 4, Ir[SC3H(Ph-3)(CHdouble bond; length as m-dashCHPh-5)]HI(PPh3)2 (5) confirms the unusual 2-metallathiophene structure. Treatment of IrCl(CS)(PPh3)2 with Hg(CHdouble bond; length as m-dashCPh2)2 produces both a coordinatively unsaturated 1-iridaindene, Ir[C8H5(Ph-3)]Cl(PPh3)2 (6) and a chelated dithiocarboxylate complex, Ir(κ2-S2CCHdouble bond; length as m-dashCPh2)Cl(CHdouble bond; length as m-dashCPh2)(PPh3)2 (7). X-ray crystal structure determinations for 6 and 7 are reported.