1,2-Dichloroethane → (R)-methyl 1-((S)-2-(benzyloxycarbonylamino)-3-(tert-butoxycarbonylamino)propanoyl)piperidine-2-carboxylate

To a suspension of (S)-2-(benzyloxycarbonylamino)-3-(tert-butoxycarbonylamino)propanoic acid (2.26 g, 6.68 mmol) in DCM (50 mL) was added (R)-methyl piperidine-2-carboxylate HCl salt (1.00 g, 5.57 mmol), followed by EDC (1.60 g, 8.35 mmol), HOBT (1.71 g, 11.1 mmol), and TEA (2.33 mL, 16.7 mmol). The reaction mixture was stirred at rt for 6 hr. The reaction mixture was diluted with water and extracted with EtOAc (2×30 mL). The combined EtOAc layers were washed with water and saturated aqueous NaCl, dried over Na2SO4, filtered and concentrated. The crude product was purified using silica gel chromatography (ISCO system) eluting with a gradient of 30-70% EtOAc/Hex to give (R)-methyl 1-((S)-2-(benzyloxycarbonylamino)-3-(tert-butoxycarbonylamino)propanoyl)piperidine-2-carboxylate (1.80 g, 3.88 mmol, 69.8% yield) as a white foam. Anal. Calcd. for C23H33N3O7 m/z 463.5. found: 464.3 (M+H)+.

1. extractionextracted with EtOAc (2×30 mL)
2. washThe combined EtOAc layers were washed with water and saturated aqueous NaCl
3. dry with materialdried over Na2SO4
4. filtrationfiltered
5. concentrationconcentrated
6. customThe crude product was purified
7. washeluting with a gradient of 30-70% EtOAc/Hex

ORD record

ord-169f628cafc5417dab8706ddc593e920

Source dataset

uspto-grants-2016_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09346852B2