101623-69-2

A clear, colourless to pale yellow liquid used as an intermediate in Gabapentin, an API.

To an ice cold reaction mixture containing p-nitrophenol (1.39 g, 10 mmol) and pyridine (0.81 g, 10 mmol) in dichloromethane (60 mL) was added 1-chloroethyl chloroformate (1.2 mL, 11 mmol). The mixture was stirred at 0° C for 30 min and then at room temperature for 1 hour. After removing the solvent under reduced pressure, the residue was dissolved in ether, washed with water, 10percent citric acid and water. The ether layer was dried over Na2SO4and evaporated under reduced pressure to give 2.4 g (97percent) of 1-Chloroethyl (4-nitrophenyl) carbonate as an off-white solid.