Metallaheteroborane chemistry—II. Synthesis and characterization of [Ir(dppe)2(X)2][SeB10H11{X= O(I) or H(II} complexes. Crystal and molecular structure of cis-bis[1,2- bis(diphenylphosphino)ethane]dihydroiridium(III) selenaundecahydrodecaborate(1−), (II)

Abstract

Abstract The reaction of [Ir(dppe)2]Cl with [Et4N] [SeB10H11] in THF followed by work up in air gave [Ir(dppe)2O2] [SeB10H11] (I) in 46% yield. Heating (I) at 120°C for 7 h under reduced pressure gave [Ir(dppe)2H2] [SeB10H11 (II) as the major product. Compounds (I) and (II) were characterized spectroscopically (IR, 1H, 11B, 31P NMR). Crystals of (II) are triclinic, space group P 1 with two formula units and a molecule of dichloromethane in the asymmetric unit. Cell data are a = 18.308(4), b = 27.580(4), c = 12.017(2) A, α = 98.33(1), β = 95.94(2), γ = 105.29(1)°. The structure was refined with 7025 observed reflections to R = 0.069 by full matrix least-squares calculations. The [Ir(dppe)2H2]+ cations have distorted octahedral coordination with cis H atoms and Ir-P(trans to H) (2.359 A) larger than IrP(trans to P) (2.314 A). The cations differ in their orientation of CH2CH2 moieties in the dppe ligands. The anions have their unique Se atoms scrambled over several sites in the [SeB10H11]− cages with one cage being more disordered than the other.