Triethylamine → Methyl 3-Cyano-2-[(2-{[(2S)-2-(3,4-dichlorophenyl)pent-4-enyl]amino}ethyl)thio]-1-naphthoate Hydrochloride

Participants

Reaction Steps

To a solution of methyl 2-[(2-aminoethyl)thio]-3-cyano-1-naphthoate hydrochloride (Intermediate 3, 530 mg, 1.65 mmol) in methanol (100 mL) was added triethylamine (250 μL, 1.82 mmol). After 30 min (2S)-2-(3,4-dichlorophenyl)pent-4-enal {Intermediate 4, 525 mg (72% pure), 1.65 mmol} and the pH was adjusted to 4-5 with acetic acid. After 30 min a solution of sodium cyanoborohydride (200 mg, 3.20 mmol) in methanol (2 mL) was added and reaction mixture stirred at ambient temperature overnight. Reaction mixture volume reduced by half and 20% K2CO3 (50 mL) was added. Reaction mixture volume reduced further to about 50 mL and methylene chloride (100 mL) was added. The organic layer was washed with brine, dried (Na2SO4), and evaporated to an oil which was chromatography on silica gel in 5% MeOH/CHCl3 to give 730 mg of the free base. The free base was dissolved in HCl/MeOH and evaporated to dryness to give 780 mg of the title compound.

Provenance & Evidence