4-Chlorobenzoic Acid → HCID 13393254, compound

Participants

Reaction Steps

1.14 Grams of 2-amino-3-(Oxindol-3-yl)propionic acid hydrochloride prepared in reference example 1, and 0.8 ml of triethylamine were suspended in 10 ml of tetrahydrofuran, then under stirring condition at a room temperature, a solution of 1.0 g of diethyl chlorophosphate with 10 ml of tetrahydrofuran was added dropwise thereto, and the reaction mixture was stirred at a room temperature for 3 hours. A solution of 1.0 g of p-chlorobenzoic acid with 10 ml of tetrahydrofuran was added dropwise to the reaction mixture, and the whole reaction mixture was stirred at a room temperature for additional 10 hours. After the reaction was completed, the crystals formed were removed by filtration, and the filtrate was concentrated, to the residue thus obtained was poured a saturated sodium bicarbonate aqueous solution, then the mixture was extracted with chloroform. The organic layer was washed with water and a saturated sodium chloride aqueous solution, then the chloroform layer was dried with anhydrous sodium sulfate, and the solvent was removed by evaporation. The thus obtained residue was recrystallized from methanol-water to obtain 0.75 g of 2-(4-chlorobenzoylamino)-3-(oxindol-3-yl)propionic acid 1/4-hydrate in the form of colorless powdery substance. Melting point: 133°-135° C. (decomp.) [α]D25 -50.3° (C=1, methanol)

Provenance & Evidence