Dimethyl Sulfate → Ondansetron

Participants

Reaction Steps

A solution of 1,2,3,9-tetrahydro-3-[(2-methyl-1H-imidazol-1-yl)methyl]-4H-carbazol-4-one (1.0 g) in dry dimethylformamide (10 ml) was added dropwise under nitrogen to a stirred, ice-cooled suspension of sodium hydride (80% in oil; 0.11 g) in dry dimethylformamide (5 ml). After 0.5 h dimethylsulphate (0.34 ml) was added, and the solution stirred at room temperature for 4 h. The resultant solid was filtered off, washed with ice-cold dry dimethylformamide (2×5 ml) and dry ether (3×15 ml) and dried to give the title compound as a solid (0.25 g) m.p. 223°-224° (dec).

Provenance & Evidence