2,2,2-Trichloroethyl chloroformate → Ethyl 4-(3,4-dichlorophenyl)pyrrolidine-3-carboxylate

Participants

Reaction Steps

To a solution of (3SR,4RS)-1-benzyl-4-(3,4-dichloro-phenyl)-pyrrolidine-3-carboxylic acid ethyl ester (2.50 g, 6.61 mmol) in CH3CN (55 mL) was added 2,2,2-trichloroethyl chloroformate (1.34 mL, 9.91 mmol) and stirring was continued for 4 hours at RT. Volatiles were removed under vacuo, and the residue was dissolved in AcOH (25 mL). Then Zn dust (1.20 g) was added portion wise. After three hours at RT the reaction mixture was filtered on celite, the solvent removed under vacuo followed by an extraction with EtOAc/aq. NaHCO3 (basic pH). The organic phases were dried on Na2SO4 and column chromatography (SiO2, CH2Cl2/MeOH 9:1) yielded 1.85 g (97%) of the title compound as a light yellow oil. ES-MS m/e: 288.1 (M+H+).

Provenance & Evidence