Diisopropylethylamine → 1-(SR)-((t-Butoxycarbonyl)amino)-3-(SR)-((4-(N-(4-nitrobenzyloxycarbonyl)-N-(allyl)amino)piperidin-1-yl)methyl)-4-(SR)-phenylcyclopentane

Participants

Reaction Steps

To a solution of 1-((SR)-((t-butoxycarbonyl)amino)-3-(SR)-(formyl)-4-(SR)-phenylcyclopentane (from Step G, derived from Higher Rf isomer in Step E) (30 mg, 0.11 mmol) in 1,2-dichloroethane (3 mL) was added 4-(N-(4-nitrobenzyloxycarbonyl)(N-allyl)amino)piperidine hydrochloride (45 mg, 0.126 mmol) and DIPEA (0.022 mL, 0.126 mmol). After 15 min, sodium triacetoxyborohydride (45 mg, 0.22 mmol) was added and the reaction was stirred at RT for 6 h. The reaction was diluted with methylene chloride, quenched with aq. sodium carbonate and extracted 3 times with methylene chloride. The organic layers were each washed with brine, dried over sodium sulfate, combined and concentrated in vacuo. The residue was purified by Prep TLC eluting with 5% methanol in methylene chloride to give the title product (66 mg) as the free amine.

Provenance & Evidence