A Methylated Oxo-Thio Stannate Cluster from a Non-Innocent Ionic Liquid

A new salt of the alkylated oxo-thio stannate cluster [Sn10O4S16(SMe)(4)](4-), (C(4)C(4)C(1)Im)(4)[Sn10O4S16(SMe)(4)] (1), was obtained by ionothermal treatment of K-4[SnS4]center dot 4H(2)O. The reaction was carried out in the ionic liquid 1,3-dibutyl-2-methylimidazolium chloride, (C(4)C(4)C(1)Im)Cl, which proved to be non-innocent against the chalcogenido metallate species in the reaction mixture. In continuation of our first studies on alkylation of very weakly nucleophilic chalcogenido metalate anions, this study served to prove that an N-bonded alkyl group is selectively released from the imidazolium cation of the ionic liquid, and it served to show that methylation is favored over butylation. The title compound is one of the rare cases, in which the cations of the salt, which stem from the ionic liquid, could be crystallographically determined without problems.