LAUSR

[8,8-(dppe)-nido-8,7-NiSB9H11] 1, [7-Et-8,8-(dppe)-nido-8,7-NiSB9H10] 2, [9-Et-8,8-(dppe)-nido-8,7-NiSB9H10] 3, and [2,2-(dppe)-closo-2,1-NiSB8H8] 4, are isolated from the reaction between Cs[arachno-SB9H12], Li[BHEt3] and [NiCl2(dppe)] at low temperature in yields of 30%, 1%, 0.1% and < 1%, respectively. The arachno-nickellathiadecaborane [6,6-(dppe)-arachno-6,9-NiSB8H10] 5 is isolated from the reaction between [(N,N,N',N' tetramethylnaphthalene-1,8-diamine)H][SB8H11], Li[BHEt3] and [NiCl2(dppe)] at low temperature (75% yield). 1 is shown to reversibly take up NH3 in solution and the characterization of the resulting compound is discussed. 5 shows no interaction with ammonia but does reversibly take up CO to give [6,6,6-(CO)(dppe)-arachno-6,9-NiSB8H10] 7. The CO molecule is very weakly bound and is readily lost even in the solid state. Similarly to 1, the isonido-iridathiaundecaboranes [(L)2-H-isonido-IrSB9H9] (where L = PMe3 and PMe2Ph) also reversibly take up NH3 to quantitatively afford [8,8,8-(PMe3)2(NH3)-nido-8,7-IrSB9H10].NH3 8 and [8,8,8-(PMe2Ph)2(NH3)-nido-8,7-IrSB9H10] 9. The ferrathiaborane compound [1,1,3-(dppe)2-1,2-closo-FeSB9H9] 11 was isolated in trace yield when [FeCl2(dppe)] was used as the starting metal complex. Where appropriate, the compounds are characterized by single-crystal X-ray diffraction studies, multielement NMR spectroscopy together with DFT GIAO chemical shielding calculations, IR spectroscopy and elemental analyses.