Abstract

The reaction of 9-iodo-ortho-carborane with n-butylmagnesium bromide affords 9-n-butyl-ortho-carborane. The reaction of the latter with alkali in boiling ethanol gives new nido-carborane [5-Bu-7,8-C₂B₉H₁₁]^– (I) containing the n-butyl substituent at the lower rim of the basket. The reaction of compound I with RuCl₂(PPh₃)(Ph₂P(CH₂)₄PPh₂) results in the formation of the corresponding ruthenium(IV) closo complex 3,3-(Ph₂P(CH₂)₄PPh₂)-3-H-3-Cl-9-Bu-closo-3,1,2-RuC₂B₉H₁₀ (II) characterized by 2D NMR spectroscopy. On heating compound II can react with carbon tetrachloride to form the 17-electron complex 3,3-(Ph₂P(CH₂)₄PPh₂)-3-Cl-9-Bu-closo-3,1,2-RuC₂B₉H₁₀ (III). The structure of complex III is solved by X-ray diffraction (XRD) (CIF file CCDC no. 2180761). The electrochemical studies show that complex III undergoes the reversible transition Ru(II) → Ru(III) similarly to the earlier studied ruthenacarboranes.