1-Chloroethyl chloroformate → Ethyl 1-benzylpiperazine-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

Under argon at 0° C., to a solution of ethyl 1,4-dibenzylpiperazine-2-carboxylate (10 g) in dichloroethane (40 mL) a solution of 1-chloroethyl chloroformate (4.73 mL) in dichloroethane (14 mL) was added dropwise over a period of 10 min. The reaction mixture was stirred for 15 minutes at 0° C., and then heated to reflux overnight. The solvent was evaporated and the crude material was dissolved in ethanol and heated at reflux overnight. The solvent was evaporated and the residue was dissolved in water and extracted with diethyl ether (×2) and CH2Cl2 (×2). A saturated solution of NaHCO3 was then added to the water phase, and the inorganic phase was extracted with CH2Cl2 (×2). The organic layers were then combined, washed with brine, dried (Na2SO4), filtered and concentrated to give 1-benzyl-piperazine-2-carboxylic acid ethyl ester as crude product, MS: 248.9 ([M+H]+).

Provenance & Evidence