Novel trialkylstibane iridium(I) and iridium(III) complexes including the x‐ray crystal structure of five‐Coordinate [IrCl(C2H4)2(SbiPr3)2]

The reaction of [IrCl(C8H14)2]2 (2) with SbiPr3 in the presence of H2 yields the dihydridoiridium(III) complex cis,mer‐[IrH2Cl(SbiPr3)3] (3) which on treatment with CO and with HCCR (R = Ph, CO2Me) affords the octahedral derivatives [IrH2Cl(CO)(SbiPr3)2] (4) and [IrHCl(CCR)(SbiPr3)3] (5, 6), respectively. The stibane ligand trans to hydride in 5 and 6 is rather labile and, therefore, 5 and 6 react with pyridine to give [IrHCl(CCR)(py)(SbiPr3)2] (7, 8). Five‐coordinate bis‐(stibane)iridium(I) complexes [IrCl(C2H4)2(SbR3)2] (10–12) were prepared from [IrCl(C2H4)2]2 (9) and four equiv. of SbR3 (R = iPr, Me, Ph). The X‐ray crystal structural analysis of 10 reveals a distorted trigonal‐bipyramidal geometry around the metal center with one stibane ligand and the two olefinic ligands in the equatorial plane. Compound 10 reacts with NaC5H5 to yield [C5H5Ir(C2H4)(SbiPr3)] (13) and with different alkynes by partial or complete displacement of the ethene ligands to give trans‐[IrCl(PhCCPh)(SbiPr3)2] (14), [IrHCl(CCTol)(C2H4)(SbiPr3)2] (15), and trans‐[IrCl‐{CC(SiMe3)R}(SbiPr3)2] (16, 17), respectively.