Ionic Liquid-Driven Formation of and Cation Exchange in Layered Sulfido Stannates – a CH2 Group Makes the Difference

Abstract

Two types of layered sulfido stannates or a molecular cluster compound are obtained upon ionothermal treatment of the simple sulfido stannate salt K4[SnS4] (Formula presented.) 4H2O that is based on binary tetrahedral [SnS4]4− anions. The formation of the respective products, novel compounds (C4C1C1Im)2[Sn3S7] (1 a), (C4C1C2Im)2[Sn3S7] (1 b), and (C4C1C2Im)2[Sn4S9] (2) with layered anionic substructures, or the recently reported compound (C4C1C1Im)4+x[Sn10O4S16(SMe)4][An]x (A) comprising a molecular cluster anion, is controlled by both the choice of the ionic liquid cation and the reaction temperature. We report the scale-up of the syntheses by a factor of 100 with regard to other reported ionothermal syntheses of related compounds, and a procedure of how to isolate them in phase-pure form – both being rare observations in chalcogenido stannate chemistry in ionic liquids. Moreover, the synthesis of compound 1 a can be achieved by rapid cation exchange starting out from 1 b, which has not been reported for organic cations in any chalcogenido stannate salt to date.