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

Temperature

100 °C

Treat a solution of 1-vinylpyrrolidin-2-one (2 g, 8.58 mmol) in dry THF (30 mL) with lithium diisopropylamide (LDA) (13 mL, 31.45 mmol) at −20° C. under N2 atmosphere and stir at the same temperature for 30 min. Then add methyl 2-bromo-4-fluorobenzoate (2 g, 8.58 mmol) and stir it over the weekend. Add an HCl (12 N, 9 mL) solution and water (12 mL). Remove the THF and add HCl (12 N, 12 mL) and water (15 mL). Heat it to 100° C. for 15 h. Cool the mixture to RT and add a 5% NaOH solution. Extract the solution with ether, dry over magnesium sulfate, and remove the solvent. Purify the residue by column chromatography (hexane to ethyl acetate) to give the title compound (0.42 g, 27%). MS (ES) m/z 244 [M+1]+.

1. customRemove the THF
2. additionadd HCl (12 N, 12 mL) and water (15 mL)
3. temperatureCool the mixture to RT
4. additionadd a 5% NaOH solution
5. extractionExtract the solution with ether
6. dry with materialdry over magnesium sulfate
7. customremove the solvent
8. customPurify the residue by column chromatography (hexane to ethyl acetate)

ORD record

ord-639640cd074d4766a5761bc9590bb3d0

Source dataset

uspto-grants-2011_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08063035B2