Reactions of the spiro monoanion [{(Me2N)Sb(μ-NCy)2}2Sb]− with alcohols and thiols (REH; E = O or S); syntheses of nido-[Sb3(μ-NCy)3(μ3-NCy)(ER)2] anions and the unique antimony(III) imido cubane [(2-NC5H4O)Sb(μ3-NCy)]4 (Cy= cyclohexyl)

Abstract

Reactions of Sb(NMe₂)₃ with a mixture of CyNH₂ and Prⁱ₂NM (1∶1∶1 equivalents) afforded a simple route to M[{(Me₂N)Sb(μ-NCy)₂}₂Sb] (M = Li 1·Li or Na 1·Na), containing the spiro anion [{(Me₂N)Sb(μ-NCy)₂}₂Sb]⁻1. The reactions of 1·Li with ^tBuOH/^tBuOK and with 2-HS{1-Me(imid)} (imid = imidazole) (2 equivalents) gave [K·η⁶-C₆H₅Me][Sb₃(μ-NCy)₃(μ₃-NCy)(O^tBu)₂] 2 and Li[Sb₃(μ-NCy)₃(μ₃-NCy)(S{2-Me(imid)})₂] 3, respectively, in which the spiro structure of the precursor rearranges into a nido framework. Reaction of 1·Li with HOC₅H₄N-2 led to disintegration of the Sb₃N₆ anion core and formation of the unique antimony(III) imido cubane [(2-NC₅H₄O)Sb(μ₃-NCy)]₄4. The crystal structures of the new complexes 1·Na, 3 and 4 were determined.