4-Methylmorpholine → 2-[3-(4-Bromophenoxy)-2-tert-butoxycarbonylamino-propionylamino]-3-methyl-butyric acid methyl ester

Participants

Reaction Conditions

Reaction Steps

A solution of the compound obtained in step e above (22e) (816 mg, 2.27 mmol), NMM (0.55 mL, 4.922 mmol) and HOBt (521 mg, 3.864 mmol) in DMF (10 mL) was stirred at 0° C. for 10 minutes, then the reaction was cooled to −15° C., and EDCI (478 mg, 2.497 mmol) was added. The reaction was stirred for 30 minutes at −15° C. and then allowed to warm to room temperature, (R)-methyl 2-amino-3-methylbutanoate hydrochloride (417 mg, 2.497 mmol) was added. After being stirred overnight, the reaction mixture was concentrated under vacuum; the residue was diluted with EtOAc and washed with brine. The combined organic layers were dried and concentrated; the residue was purified by silica gel column chromatography to give the title compound as colourless oil (900 mg, 84%).

Provenance & Evidence