Aspirin → 3-(Benzyloxycarbonylamino)propyl 2-acetoxybenzoate
Reaction equation
[C:1]([O:4][C:5]1[CH:13]=[CH:12][CH:11]=[CH:10][C:6]=1[C:7]([OH:9])=[O:8])(=[O:3])[CH3:2].C(N(CC)CC)C.ClC(OCC)=O.O[CH2:28][CH2:29][CH2:30][NH:31][C:32](=[O:41])[O:33][CH2:34][C:35]1[CH:40]=[CH:39][CH:38]=[CH:37][CH:36]=1>C(Cl)Cl>[C:1]([O:4][C:5]1[CH:13]=[CH:12][CH:11]=[CH:10][C:6]=1[C:7]([O:9][CH2:28][CH2:29][CH2:30][NH:31][C:32]([O:33][CH2:34][C:35]1[CH:36]=[CH:37][CH:38]=[CH:39][CH:40]=1)=[O:41])=[O:8])(=[O:3])[CH3:2]Participants
Conditions
- Temperature
- 0 °C
Procedure
To a solution of 2-acetoxybenzoic acid (2.0 g, 11.1 mmol) and triethylamine (1.8 mL, 11.1 mmol) in CH2Cl2 (40 mL) at 0° C. was slowly added ClCO2Et (1.1 mL, 167 mmol). The reaction mixture was stirred (0° C., 2 h) and filtered. The filtrate was added to a solution of benzyl 3-hydroxypropylcarbamate (2.1 g, 10.0 mmol) and triethylamine (15 mL) in CH2Cl2 (40 mL). The reaction mixture was stirred (RT, 4 h) and quenched with H2O (50 mL). The organic layer was washed with 1 M HCl, saturated Na2CO3 (30 mL) and H2O (50 mL). The organic solution was dried over MgSO4 and concentrated under reduced pressure. The residue was purified by silica chromatography, (PE-EtOAc, 5:1) to afford 3-(benzyloxycarbonylamino)propyl 2-acetoxybenzoate (2.0 g, 54%) as a colorless oil. Mass calculated for C20H21NO64=371.38. found: [M+H]+=372.3.
Workup
- customat 0° C.
- filtrationfiltered
- stirringThe reaction mixture was stirred (RT, 4 h)
- customquenched with H2O (50 mL)
- washThe organic layer was washed with 1 M HCl, saturated Na2CO3 (30 mL) and H2O (50 mL)
- dry with materialThe organic solution was dried over MgSO4
- concentrationconcentrated under reduced pressure
- customThe residue was purified by silica chromatography, (PE-EtOAc, 5:1)
Sources & evidence
- ORD record
- ord-4e86e10dea30486098ad0bdabb61fcd4
- Source dataset
- uspto-grants-2014_05
- Patent number
- US08729293B2
Reaction notes
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