(S)-tert-butyl 2-(2-oxoethyl)pyrrolidine-1-carboxylate → tert-butyl (2S)-2-(2-hydroxyethyl)pyrrolidine-1-carboxylate

Temperature

-78 °C

To a solution of 1-BOC-2-(S)-pyrrolidineethanal (6.80 g, 26.5 mmol) in anhydrous toluene (100 mL), cooled to -78° C. was added a 1M solution of diisobutylaluminum hydride in toluene (132.5 mL, 132.5 mmol). The reaction was stirred at -78° C. for 2 hours, and diisobutylaluminum hydride solution (26.50 mL, 26.5 mmol) was added. The mixture was stirred for 2 hours, then the reaction was quenched at -78° C. with methanol (150 mL). The mixture was poured into 1M Rochelle salt (500 mL), and the emulsified solution was extracted with ethyl acetate (200 mL). The organic layer was washed with brine, dried over MgSO4, and concentrated. The residue was purified on silica gel, eluting with methanol/methylene chloride (5:95) to yield a colorless oil (3.82 g, 67%). MS (DCI/NM) m/e: 216 (M+H)+. 1HNMR (CDCl3, 300 MHz) δ: 1.47 (s, 9H), 1.58-1.76 (m, 2H), 1.82-2.05 (m, 3H), 3.31 (t, J=6.0 Hz, 2H), 3.50-3.69 (m, 2H), 4.10-4.21 (m, 1H), 4.43 (dd, J=4.0, 7.0 Hz, 1H).

1. stirringThe mixture was stirred for 2 hours
2. customthe reaction was quenched at -78° C. with methanol (150 mL)
3. additionThe mixture was poured into 1M Rochelle salt (500 mL)
4. extractionthe emulsified solution was extracted with ethyl acetate (200 mL)
5. washThe organic layer was washed with brine
6. dry with materialdried over MgSO4
7. concentrationconcentrated
8. customThe residue was purified on silica gel
9. washeluting with methanol/methylene chloride (5:95)

ORD record

ord-cba2b7d5b5654346a75d48f3956ba223

Source dataset

uspto-grants-1999_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05914328