Benzylamine → tert-butyl (2S,4S)-4-amino-2-methylpyrrolidine-1-carboxylate

Temperature

100 °C

To a 90 g (0.322 mol) sample of (2S,4R)-1BOC-4-methanesulfonyloxy-2-methylpyrrolidine, prepared as described in U.S. Pat. No. 4,962,112, was added 345 g (3.22 mol) of benzylamine, and the solution was heated at 100° C. under N2 for 8 hours. The solution was cooled to room temperature and the excess benzylamine removed under vacuum. The residue was dissolved in ethyl acetate and washed with water. The product was then extracted into 1.0M citric acid, which was then adjusted to pH 11.5 with conc. ammonium hydroxide solution. The product was extracted into ethyl acetate, which was dried over Na2SO4, filtered, and concentrated. After drying, 76.2 g (81.5% yield) of the title product was obtained as a yellow oil.

1. temperatureThe solution was cooled to room temperature
2. customthe excess benzylamine removed under vacuum
3. dissolutionThe residue was dissolved in ethyl acetate
4. washwashed with water
5. extractionThe product was then extracted into 1.0M citric acid, which
6. extractionThe product was extracted into ethyl acetate, which
7. dry with materialwas dried over Na2SO4
8. filtrationfiltered
9. concentrationconcentrated
10. customAfter drying

ORD record

ord-a8e6b49cb3844f039d37c7e49474f931

Source dataset

uspto-grants-1993_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05252747