Acetic Acid → Tert-butyl 4-cyclobutylpiperazine-1-carboxylate

Participants

Reaction Steps

Piperazine-4-carboxylic acid tert-butyl ester (3.74 g), cyclobutanone (3.00 mL), and acetic acid (1.15 mL) were dissolved in methanol (100 mL). To the resultant solution, sodium cyanoborohydride (1.89 g) was added at room temperature, followed by stirring for 3 hours. The solvent was evaporated under reduced pressure, and the residue was partitioned by use of ethyl acetate and saturated aqueous sodium hydrogencarbonate. The organic layer was washed with saturated brine, and then dried over magnesium sulfate anhydrate, followed by filtration. The solvent was evaporated under reduced pressure. The residue was purified through silica gel column chromatography (chloroform-methanol), to thereby give the title compound as an oily product (4.43 g, 92%).

Provenance & Evidence