4-Amino-1,2,2,6,6-pentamethylpiperidine → (2Z,4E)-5-(5,6-Dichloro-1H-indol-2-yl)-2-methoxy-N-(1,2,2,6,6-pentamethyl piperidin-4-yl)-2,4-pentadienamide

Participants

Reaction Steps

A solution of (2Z,4E)-5-(5,6-dichloro-1H-indol-2-yl)-2-methoxy-2,4-pentadienoic acid (736 mg, 3.65 mmol), 4-amino-1,2,2,6,6-pentamethylpiperidine (620 mg, 3.65 mmol), 1-hydroxy-7-azabenzotriazole hydrate (474.5 mg, 3.65 mmol) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (693.5 mg, 3.65 mmol) in DMF (2 ml) was stirred at RT overnight. The solution was poured into brine (20 ml) and repeatedly extracted with EtOAc. The organic phase was washed with 5% aq. CaCO3, dried (MgSO4) and evaporated under vacuum. The residue was chromatographed on silica gel using ethyl acetate:methanol:aq. ammonia (32%) 90:10:2 as eluent mixture. The collected fractions produced the pure title compound (0.8, yield 73%) as yellow crystals, m.p.=212° C.

Provenance & Evidence