Aspirin → 3-(Benzyloxycarbonylamino)propyl 2-acetoxybenzoate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

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 1M aqueous HCl, saturated aqueous 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 gel 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.

Herkunft & Nachweise