Hydrochloric Acid → 5-(2,5-difluorophenyl)-3,4-dihydro-2H-pyrrole

Temperature

70 °C

In step 6A-2, concentrated hydrochloric acid (23 mL, 260 mmol) was added to a solution of tert-butyl 2-(2,5-difluorophenyl)-2-hydroxypyrrolidine-1-carboxylate (6-3) (15.6 g, 52 mmol) in methanol. The reaction mixture was heated to 70° C. while stirring and was then stirred at 70° C. for 6 hours. The reaction mixture was cooled to room temperature and neutralized with a 7.5 M solution of sodium hydroxide (35 mL, 263 mmol). The methanol was removed and the resulting slurry was reconstituted with ethyl acetate (250 mL). The organic layer was washed with brine (3×150 mL), and then dried with sodium sulfate. The ethyl acetate was then removed to yield 5-(2,5-difluorophenyl)-3,4-dihydro-2H-pyrrole (6-4) as a light yellow oil. m/z=182.2 [M+1].

1. stirringwas then stirred at 70° C. for 6 hours
2. temperatureThe reaction mixture was cooled to room temperature
3. customThe methanol was removed
4. washThe organic layer was washed with brine (3×150 mL)
5. dry with materialdried with sodium sulfate
6. customThe ethyl acetate was then removed

ORD record

ord-9f050930f2e04af2a681acc76511d7db

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08507488B2