Participants
| Role | Name | HCID | Charge |
|---|
| Reactant | Triethylamine | HCID 8471 | — |
| Reactant | Ethyl Acetate | HCID 8857 | — |
| Reactant | Ethyl chloroformate | HCID 10928 | — |
| Reactant | HCID 86621601 | HCID 86621601 | — |
| Solvent | Dichloromethane | HCID 6344 | — |
| Solvent | Hexane | HCID 8058 | — |
| Product | HCID 86621602 | HCID 86621602 | 90% |
Reaction Steps
To a mixture of (1R,2R)-2-acetyloxy-1-methylpropyl (2S)-3-(3,4-dihydroxyphenyl)-2-[(tert-butoxy)carbonylamino]propanoate (34) (0.5 g, 1.2 mmol) and ethyl chloroformate (0.3 mL, 3.0 mmol) in anhydrous dichloromethane, triethylamine (0.4 mL, 3.0 mmol) was added at 0° C. The reaction mixture was stirred at 0° C. for 1 hour. The solution was partitioned between dichloromethane and 10% citric acid and washed with water. The organic layer was dried over MgSO4, and concentrated to dryness. Chromatography (25% ethyl acetate in hexane) provided the title compound (35) (0.6 g, 90% yield) as a white, foamy solid. 1H NMR (400 MHz, CDCl3): δ 1.11 (d, J=6.4 Hz, 3H), 1.13 (d, J=6.4 Hz, 3H), 1.34 (t, J=7.2 Hz, 3H), 1.35 (t, J=7.2 Hz, 3H), 1.40 (s, 9H), 2.02 (s, 3H), 3.02 (dd, J=14.0, 6.8 Hz, 1H), 3.07 (dd, J=14.0, 6.8 Hz, 1H), 4.27 (q, H=7.2 Hz, 2H), 4.28 (q, J=7.2 Hz, 2H), 4.51 (dd, J=14.0, 6.8 Hz, 1H), 4.93 (m, 2H), 5.03 (d, J=8.4 Hz, 1H, NH), 7.03 (dd, J=8.0, 2.0 Hz, 1H), 7.06 (d, J=2.0 Hz, 1H), 7.16 (d, J=8.0 Hz, 1H). MS (ESI) m/z 578.1 (M+Na)+.
Provenance & Evidence
| DOI | 10.6084/m9.figshare.5104873.v1 |
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| Patent number | US08324273B2 |
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| Source dataset | uspto-grants-2012_12 |
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| ORD ID | ord-b86b265b982b48bcb09635f7dbc5a3d2 |
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| Source note | uspto-grants-2012_12 |
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