Potassium Hydroxide → 2-Fluoro-5-hydrazinylpyridine

Participants

Reaction Conditions

Reaction Steps

A solution of sodium nitrite (345 mg, 5.00 mmol) in water (2.5 ml) was added dropwise to a vigorously stirred solution of 6-fluoropyridin-3-amine (561 mg, 5 mmol) in 6N hydrochloric acid (5 ml) at 0° C. The mixture was stirred at 0° C. for 1 hour, then a solution of tin (II) chloride dihydrate (2.82 g, 12.5 mmol) in 6N hydrochloric acid (5 ml) was added dropwise whilst adding small pieces of ice to keep the inner temperature below 5° C. The formation of a foamy layer was observed during the addition and stirring was continued at 0° C. for 3 h. The mixture was made alkaline (pH=14) by addition of 40% aqueous solution of potassium hydroxide and extracted with ethyl acetate (5 times 15 ml). The combined organic extracts were dried over sodium sulfate, the drying agent was filtered off and the solvent was removed under reduced pressure to afford 250 mg (39%) of the target compound as a pale-yellow solid.

Provenance & Evidence