Water → (R)-benzyl 3-(tert-butoxycarbonyl(methyl)amino)piperidine-1-carboxylate

Temperature

0 °C

A solution of (R)-benzyl 3-(tert-butoxycarbonylamino)piperidine-1-carboxylate (5.00 g, 14.95 mmol) in dry DMF (50 mL) was added dropwise to a suspension of sodium hydride 60% in mineral oil (0.7176 g, 17.94 mmol) in dry DMF (10 mL). The mixture was stirred at 0° C. for 1 hour and allowed to stir at room temperature for 2 hours. Then the mixture was cooled to 0° C. and treated dropwise with iodomethane (1.024 mL, 16.45 mmol). The reaction mixture was stirred at 0° C. for 1 hour and allowed to warm to room temperature over 18 hours. Water (40 mL) was added, and the mixture was extracted into EtOAc (3×50 mL). The organic layers were combined, washed with water (3×20 mL), dried (MgSO4), filtered, and concentrated in vacuo. The residue obtained was purified by flash chromatography on silica gel (Biotage Flash 40M+) eluting with 20% EtOAc/hexane (1.25 L) to provide (R)-benzyl 3-(tert-butoxycarbonyl(methyl)amino)piperidine-1-carboxylate (4.10 g, 79% yield) as an oil. LCMS (APCI+) m/z 349 (M+H)+.

1. stirringto stir at room temperature for 2 hours
2. temperatureThen the mixture was cooled to 0° C.
3. stirringThe reaction mixture was stirred at 0° C. for 1 hour
4. temperatureto warm to room temperature over 18 hours
5. extractionthe mixture was extracted into EtOAc (3×50 mL)
6. washwashed with water (3×20 mL)
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. concentrationconcentrated in vacuo
10. customThe residue obtained
11. customwas purified by flash chromatography on silica gel (Biotage Flash 40M+)
12. washeluting with 20% EtOAc/hexane (1.25 L)

ORD record

ord-2ce902efb1724726b8b7efff8efada6c

Source dataset

uspto-grants-2015_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08981085B2