Ammonium Hydroxide → Citalopram

Participants

Reaction Conditions

Reaction Steps

5-Carboxy-1-(4-fluorophenyl)-1-(3-dimethylaminopropyl)-1,3-dihydro-isobenzofuran (5 g, 0.015 mole) and sulfamide (1.65 g, 0.017 mole) were dissolved in sulfolane (15 mL). Thionylchloride (2.25 g, 0.019 mole) was added at room temperature and the temperature of the reaction mixture was raised to 130° C. for 2 hours. The reaction mixture was allowed to cool to 75° C. and water (25 mL) was added. The temperature was held at 75° C. for 15 min, and then the reaction mixture was cooled to room temperature. pH was ajusted to 9 with ammonium hydroxide and then n-heptane (75 mL) was added. The temperature was raised to 70° C. and the hot n-heptane layer was isolated from which the title compound crystallised on cooling. Yield 3.77 g. Purity (HPLC peak area)>97%.

Provenance & Evidence