Hydrochloric Acid → HCID 18333146, compound

Participants

Reaction Steps

10% Pd-C (200 mg) and concentrated hydrochloric acid (0.3 ml) were added to a methanol (25 ml) solution of 4-benzyl-1-formyl-2-(pyrrolidin-1-yl)methyl-1,2,3,4-tetrahydroquinoxaline (500 mg). The reaction mixture was subjected to catalytic hydrogenation at room temperature under 4.5 atmospheric pressure for 2 hours. The catalyst was removed by filtration, and the filtrate was concentrated. 10% Aqueous potassium carbonate solution was added to the residue, which was extracted with ethyl acetate. The organic layer was washed with a saturated aqueous sodium chloride solution, then dried and concentrated to give 1-formyl-2-(pyrrolidin-1-yl)methyl-1,2,3,4-tetrahydroquinoxaline (360 mg). Oxalyl chloride (0.19 ml) was added to a THF (5 ml) solution of 3-(4-biphenylyl)propionic acid (410 mg) under ice-cooling, to which was added DMF (one drop). The reaction mixture was stirred at room temperature for 30 minutes, which was concentrated. The residue was again dissolved in THF, which was concentrated. The residue was dissolved in THF (7 ml), which was added dropwise to a THF (7 ml) solution of 1-formyl-2-(pyrrolidin-1-yl)methyl-1,2,3,4-tetrahydroquinoxaline (360 mg) and triethylamine (0.31 ml) underice-cooling. The reaction mixture was stirred at the same temperature for one hour. Water was added to the reaction mixture, which was extracted with ethyl acetate. The organic layer was washed with a saturated aqueous sodium chloride solution, then dried and concentrated. The residue was purified by alumina column chromatography (eluent: hexane to hexane/ethyl acetate=4/1), which was converted into its oxalate. The crystals were washed with IPE to give the entitled compound (350 mg).

Provenance & Evidence