4-Methylmorpholine → N-Benzenesulfonyl-(L)-prolyl-2-amino-2-norbornanecarboxylic acid, methyl ester

Participants

Reaction Steps

To a solution of 2-amino-2-norbornanecarboxylate, methyl ester hydrochloride (400 mg, 2.0 mmol), N-benzenesulfonyl-(L)-proline (510 mg, 2.0 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (306 mg, 2.0 mmol), 1-hydroxbenzotriazole (202 mg, 2.0 mmol) in 4 mL of tetrahydrofuran at 0° C. was added N-methyl morpholine (0.22 mL, 2.0 mmol). After 15 min at 0° C., the reaction mixture was stirred at room temperature for 16 h, and was concentrated in vacuo. The residue was purified by flash column chromatography on silica gel eluted with 10:1 methylene chloride/ethyl acetate to give the title compound (478 mg, 59%) as a mixture of diastereomers.

Provenance & Evidence