Yield:-

Reaction Conditions:

in toluene at 20;Inert atmosphere;Cooling with ice;

Steps:

Synthesis of pyrrolidinium based ionic liquids

General procedure: N-methyl-2-pyrrolidone (9.9 g, 0.1 mol) was dissolved in toluene (50 ml) and stirred for 5 min, under argon atmosphere. Methanesulfonic acid (9.6 g, 0.1 mol) was dropped slowly in to the flask over a period of 30 minute in an ice bath. The reaction was continued for another 6h at room temperature. Toluene was removed under reduced pressure and content was further dried under vacuum at 80 °C for 3h and was stored in dry box for further use.

References:

Garg, Bhaskar;Ling, Yong-Chien [Tetrahedron Letters,2012,vol. 53,# 42,p. 5674 - 5677] Location in patent:supporting information