Methyl iodide → 4-Bromo-6-chloro-2-methyl-2,3-dihydropyridazin-3-one

Participants

Reaction Steps

A 250-mL single-necked round bottomed flask equipped with a magnetic stirrer was purged with nitrogen and charged with 24 (1.00 g, 4.77 mmol) and DMF (15 mL). Sodium hydride (60% by weight in oil: 229 mg, 5.73 mmol) was added in one portion. After stirring at room temperature for 10 minutes, iodomethane (1.02 g, 7.16 mmol) was added and the reaction stirred at room temperature for 1.5 h. The reaction was then quenched with aqueous saturated sodium bicarbonate (10 mL) and the resulting solution poured into water (150 mL). The mixture was then extracted with ethyl acetate (250 mL). The organic layer was dried over sodium sulfate. The drying agent was then removed by filtration, and the filtrate was concentrated under reduced pressure to residue. Purification by column chromatography afforded 25 in a 68% yield (722 mg) as a white solid: mp 107-108° C.; 1H NMR (300 MHz, CDCl3) δ 7.62 (s, 1H), 3.81 (s, 3H).

Provenance & Evidence