Access to pure and highly volatile hydrochalcogenide ionic liquids.

The reaction of methylcarbonate ionic liquids with H2S or H2Se offers a highly selective synthesis of analytically pure, well-defined and soluble hydrosulphide and hydroselenide organic salts of general interest. Among them, imidazolium hydrochalcogenides show an astonishingly high volatility for cation-aprotic ILs, which allows their quantitative sublimation below 100 °C/10−2 mbar and actually results in ionic single crystal growth from the gas phase. Vaporisation and decomposition characteristics were investigated by isothermal TGA measurements and DFT calculations.