Benzyl chloroformate → (7S,10S,13S)-13-Benzyloxycarbonylamino-10-isobutyl-9,12-dioxo-2-oxa-8,11-diaza-bicyclo-[13.2.2]nonadeca-1(18),15(19),16-triene-7-carboxylic acid methyl ester

Participants

Reaction Steps

Amine 6 (4.00 g, 8.78 mmol) was dissolved in anhydrous DMF (30 mL). Benzyl chloroformate (1.88 mL, 13.2 mmol) and DIPEA (6.11 mL, 35.1 mmol) were added and the reaction mixture was stirred at rt for 18 h before being partitioned between chloroform and 1M hydrochloric acid. The aqueous phase was extracted three more times with chloroform and the combined organic extracts were dried (MgSO4), filtered and concentrated in vacuo. Purification was achieved using flash chromatography, eluting with a gradient of 15% EtOAc/DCM to 50% EtOAc/DCM to yield an off-white solid, 2.10 g, 43%. Rf=0.43 (30% EtOAc/DCM).

Provenance & Evidence