Ionic liquid cations as methylation agent for extremely weak chalcogenido metalate nucleophiles.

Selective in situ methylation of terminal chalcogenide ligands of molecular chalcogenido metalate anions in ionothermal reactions with alkylimidazolium-based ionic liquids yields a series of organo-functionalized chalcogenido metalate compounds. We present the syntheses and crystal structures of (C4C1C1Im)4+x [Sn10S16O4(SMe)4][An] x (1a-1f), (dmmpH)6[Mn4Sn4Se13(SeMe)4] (2), and (C n C1Im)6[Hg6Te10(TeMe)2] (3a, 3b). The methylation was confirmed by Raman spectroscopy, and the optical absorption properties of the methylated compounds were determined and compared to purely inorganic analogs.