Reactions of carbon disulfide with open nido-6-iridadecaboranes. The formation of closed ten-vertex cluster compounds with boron-to-metal dithioformate bridges and a novel isocloso→closo cluster conversion

Abstract

The compounds [6-H-6,6-(PPh₃)₂-nido-6-IrB₉H₁₃]1 or [6-H-6-(PPh₃)-6-(o-Ph₂P[graphic omitted]]2 reacted with refluxing CS₂ to form respectively [2,10-(PPh₃)₂-2,6;2,9-(µ-S₂CH)₂-closo-2-IrB₉H₆]4(14%) or [10-(PPh₃)-2,6;2,9-(µ-S₂CH)₂-2-(o-Ph ₂[graphic omitted]]5(17%). Compound 5(37%) was also obtained from CS₂ and [1-H-1-(PPh₃)-1-(o-Ph₂P[graphic omitted]]3 in an unprecedented isocloso→closo conversion. The new compounds 4 and 5 are characterised by NMR spectroscopy, mass spectrometry and a single-crystal X-ray diffraction analysis on 4. Compound 4 has a conventional closo ten-vertex {2-IrB₉} cluster structure with two SCHS units that bridge symmetrically from the iridium atom to the boron cluster at B(6) and B(9). Compound 5 has the same cluster structure, but now the metal-bound triarylphosphine is ortho-cycloboronated to B(1).