Hydrochloric Acid → 1-Propioloylpyrrolidine

To a stirred solution of pyrrolidine (4.2 mL, 50.0 mmol) in water (25 mL) and MeOH (35 mL) at −50° C. was added methylpropiolate (4.5 mL, 50.0 mmol) dropwise. The reaction mixture was stirred at this temperature for 5 h then diluted with DCM (200 mL). 2M aqueous HCl (200 mL) was added and the layers were separated. The aqueous layer was extracted with DCM (2×100 mL). The combined organic layers were washed with aqueous sat. NaHCO3 (200 mL), water (200 mL), then brine (200 mL), dried (Na2SO4), filtered and concentrated in vacuo to give the title compound (6.0 g, 98%) as a white solid that was used without further purification. δH (CDCl3) 3.68 (2H, t, J 6.8 Hz), 3.50 (2H, t, J 6.3 Hz), 3.04 (1H, s), 2.01-1.90 (4H, m).

1. customthe layers were separated
2. extractionThe aqueous layer was extracted with DCM (2×100 mL)
3. washThe combined organic layers were washed with aqueous sat. NaHCO3 (200 mL), water (200 mL)
4. dry with materialbrine (200 mL), dried (Na2SO4)
5. filtrationfiltered
6. concentrationconcentrated in vacuo

ORD record

ord-ecc256d397de4f7da88291afcae7638b

Source dataset

uspto-grants-2012_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08324204B2