Diisopropylethylamine → 1-Methylene-3-(SR)-((4-(N-(benzylaminocarbonyl)-N-(prop-1-yl)amino)piperidin-1-yl)methyl)-4-(SR)-phenylcyclopentane

Participants

Reaction Steps

To a solution of (+−)-trans-4-methylene-2-phenylcyclopentanecarboxaldehyde from Step C (880 mg, 4.7 mmol) in 1,2-dichloroethane (50 mL) was added 4-(N-(benzylaminocarbonyl)-(N-prop-1-yl)amino)piperidine hydrochloride (1.62 g, 5.2 mmol) and DIPEA (1.0 mL, 5.7 mmol). After 15 min, sodium triacetoxyborohydride (2.0 g, 9.5 mmol) was added and the reaction was stirred at rt for 4 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 FC eluting with 60% ethyl acetate in hexanes to give the title product (1.8 g) as the free amine. MS (NH3/ESI): m/z 448 (M +1).

Provenance & Evidence