2-Pyrrolidone → HCID 86610173, compound

To a 100 ml flask containing 8.51 g of 2-pyrrolidone (0.1 mol), 30 ml water was added and stirred for dissolution. Then 21.95 g 40% aqueous solution of tetrafluoroboric acid (0.1 mol) was added dropwise into the flask over 20 min at room temperature. Then the reaction was stirred for another 1 hour. Desired product was formed after water was removed under reduced pressure and then dried at 110° C. under 1–5 mmHg for 1 hour. The brown viscous, moisture- and water-stable liquid of 2-pyrrolidonium tetrafluoroborate was obtained with a yield of 97.2%, which has a glass transition temperature of −73° C., density of 1.46 g/ml, viscosity of 350 cP, an electrochemical window of 2.2 V, an ionic conductivity of 8.39×10−4 S/cm, and a Hammett acidic scale H0 of 0.91 using 2,4-dinitroaniline as indicator. No melting point was observed.

1. additionwas added
2. stirringThen the reaction was stirred for another 1 hour

ORD record

ord-ea394204333e4308bc13fd5e491215fb

Source dataset

uspto-grants-2007_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07220869B2