1-Hydroxybenzotriazole → HCID 18456238, compound

Participants

Reaction Steps

To a mixture of 3-(4-chlorobenzoyl)propionic acid (31.9 g, 150 mmol), DMF (200 ml), and N-hydroxybenzotriazole (40.6 g, 301 mmol) was added a solution of N-ethyl-N′-(3-dimethylaminopropyl)carbodiimide hydrochloride (28.8 g, 150 mmol) in DMF (100 ml). The mixture was stirred at room temperature for 1.5 hour, and a solution of 1-cyclopentylpiperazine (23.2 g, 150 mmol) in DCM (100 ml) was added. The mixture was stirred at room temperature for 4 hours, concentrated under reduced pressure, and the residue was distributed between ethyl acetate (1.0 I) and a saturated, aqueous NaHCO3 solution (1.0 I). Phases were separated, the organic layer was dried (MgSO4), and concentrated, and the residue was redissolved in 1 molar aqueous hydrochloric acid (150 ml). The solution was concentrated, and the residue was dried by coevaporation with ethanol. Recrystallization of the residue from ethanol yielded 31.1 g (54%) of the title compound. Concentration of the mother liquor gave additional 19.4 g (34%) of product.

Provenance & Evidence