Hydrazine hydrate (1:1) → HCID 117769950, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 5-bromo-4-chloro-1-((2S)-3-methylbutan-2-yl)-2-oxo-1,2-dihydropyridine-3-carbonitrile obtained in Step F (19.2 g) in ethanol (200 mL) was added hydrazine monohydrate (9.5 g), and the mixture was stirred at 90° C. for 1 hr. The reaction mixture was allowed to be cooled to room temperature, and the solvent was evaporated under reduced pressure. The residue was dissolved in a mixed solvent of ethyl acetate-tetrahydrofuran-water. The organic layer was separated, washed successively with saturated aqueous sodium hydrogen carbonate solution and saturated brine, and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (basic silica gel, ethyl acetate/hexane, and then ethyl acetate/methanol), and recrystallized from (ethyl acetate/diisopropyl ether) to give the title compound (15.5 g).

Provenance & Evidence