Metallaheteroborane chemistry. Part 10. Synthesis and characterisation of closo-structured rhodathiaborane complexes [1-(CO)-1-L-3-L′-1,2-RhSB₉H₈](L = L′= PPh₃; L = PMe₂Ph, L′= PMe₂Ph or PPh₃)

Polyhedral metallathiaborane chemistry: Synthesis and characterisation of metallathiaboranes based on the twelve-vertex icosahedral closo-{MSB10H10} unit, where M is Rh or Ir

“…To better characterise compound 1, as part of this present work NMR data for 1 have been gathered at higher field, and are now assigned, and compared with reported data for the other closo twelve-vertex species. The new double-cluster compound 3 (schematic cluster structure V) was characterised as such by comparison of its NMR properties with those of the previously reported and crystallographically determined [27] direct tellurium analogue [{(PPh 3 )-closoRhTeB 10 H 10 } 2 ] (8) as well as by mass spectrometry. In addition to this first-order synthesis work, and in an attempt to effect phosphine-ligand replacement, we treated the rhodathiaborane 1 with PMe 2 Ph in CH 2 Cl 2 , resulting in the synthesis of the chloro species [2, Ph) 2 -2-Clcloso-2,1-RhSB 10 H 10 ] (4) (schematic cluster structure IV, where X = Cl), isolated in 20% yield.…”

“…The interatomic distances and angles within the coordination sphere of the rhodium centre of 4 are of interest when compared to those for platinum [21] in the [2,2-(PMe 2 Ph) 2 -2,1-PtSB 10 H 10 ] species 7. Thus, whereas the rhodium-sulfur distance of 2.3629(5) Å in 4 is within the bonding range found in other polyhedral rhodathiaborane species [27][28][29], it is markedly shorter than the corresponding platinum-sulfur distance of 2.6633(7) Å in 7. Thus, in the platinum compound 7, there is a significant displacement of the platinum centre away from the sulfur atom, which generates a distortion (schematic VII) from closed icosahedral geometry as in schematic I.…”

“…Moreover, available NMR data on previous metallathiaboranes are largely based on low-dispersion spectroscopy with little assignment work. Therefore, as part of our general interest in heteroboranes [22,23] and their metal derivatives [11,13,14,16,21,[24][25][26][27][28][29], herein we report synthetic, structural and NMR studies on some new twelve-vertex rhodium and iridium metallathiaboranes incorporating the {SB 10 H 10 } ligand fragment.…”

Metallaborane Reaction Chemistry. Part 4. Polyhedral Thiametallaborane Synthesis via Direct Incorporation of Sulfur Into Metallaboranes

“…It thereby complements the hitherto predominant route [1][2][3][4][5][6][7][8][9][10][11][12][13][14]20 that involves the converse approach, viz. the reactions of metal centres with pre-formed thiaborane substrates.…”

NH3-Promoted Ligand Lability in Eleven-Vertex Rhodathiaboranes

“…3,4 This consideration prompted us to examine how we might modify the exo-polyhedral phosphine-ligand sphere in order to explore the reactivity of new phosphine-ligated derivatives of 2, the overall target being the optimization of the catalytic activity of these cluster species. In this regard, it has previously been demonstrated that the rhodathiaborane 1 undergoes facile substituion of PPh 3 by other monodentate, and also bidentate, phosphines, 5,6 and we have examined reactions of 1 and 2 with the monodentate phosphines PMePh 2 , PMe 2 Ph and PMe 3 .…”