Dimethyl sulfite → 1-Butyl-1-methylpyrrolidin-1-ium methanesulfonate

Participants

Reaction Conditions

Reaction Steps

A mixture of 11.20 g (63.0 mmol) of 1-butyl-1-methylpyrrolidinium chloride and 13.0 g (118.0 mmol) of dimethyl sulfite is stirred at 110-115° C. (temperature of the oil bath) for 48 hours under an inert-gas atmosphere (nitrogen) in a sealed reaction vessel with pressure valve for 1-1.5 bar above atmospheric pressure. The end of the reaction is determined by NMR measurement. The product is pumped off over the course of 5 hours in vacuo at 13.3 Pa and 115° C. (temperature of the oil bath), giving 14.9 g of 1-butyl-1-methylpyrrolidinium methanesulfonate as a solid. The melting point is 59-60° C. The residual chloride content is less than 5 ppm. The yield is virtually quantitative. The product is investigated by means of NMR spectroscopy.

Provenance & Evidence