Hydrazine hydrate (1:1) → 5-Chloro-2-(methylthio)pyrimidine-4-carbohydrazide

Participants

Reaction Steps

5-Chloro-2-(methylthio)pyrimidine-4-carboxylic acid (4.0 g, 19.6 mmol) and 1,1-carbonyl diimidazole (6.35 g, 39.2 mmol) were dissolved in 80 mL THF and stirred at room temperature. After 3 h, the solution was cooled in an ice bath and hydrazine hydrate (1.90 mL, 39.2 mmol) was added in one quick portion. The solution was allowed to stir for 5 h, gradually warming to room temperature. The reaction mixture was diluted with excess H2O and extracted with EtOAc several times. These organics were combined and washed with 2 N HCl. The combined aqueous layers were then basified carefully with 5 N NaOH, and extracted once again with EtOAc. This second set of organic layers was combined, dried over magnesium sulfate and concentrated under vacuum to give 2.46 g (58% yield) of product as a white solid. MS (M+H)+ 219.

Provenance & Evidence