Abstract: The invention relates to a process for the preparation of ionic liquids of general formula (cation)(R?—O—SO3). The process includes the step of treating the compound of formula (cation)(R—O—SO3) with an alcohol, or mixture of different alcohols, of the formula R?—OH optionally in the presence of a catalyst to form the desired ionic liquid and the by-product R—OH, which is optionally removed during the reaction or after completion of the reaction. The compound of formula (cation)(R—O—SO3) can be prepared by alkylating a tertiary or aromatic amine with a dialkylsulfate.

Abstract: The present invention relates to a hydroformylation method by conversion of olefins or olefinically unsaturated compounds in the presence of at least one rhodium compound and in the presence of sulfonated arylphosphines in ionic liquids, which are based on a quaternary singly-charged ammonium ion or the equivalent of a multiply charged ammonium ion and organic sulfonates or sulfates.

Abstract: An ionic liquid according to the invention is substantially halogen-free, has a low viscosity and is stable to hydrolytic degradation under test conditions. The ionic liquid is a compound of the formula (cation) (R?—O—SO3), (cation) (R?—SO3), or a mixture of the two compounds. It can be used in processes for the chemical conversion and separation of materials by employing the ionic liquid as a solvent, solvent additive, extraction agent or phase-transfer catalyst. It can also be used in a heat exchange device wherein the ionic liquid serves as a heat carrier or heat carrier additive.