Hydrazine hydrate (1:1) → HCID 178438039, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of methyl 3-oxopentanoate (2.6 g) and dimethylformamide dimethylacetal (2.8 mL) was stirred at 100° C. for 12 hr, and allowed to cool. Ethanol (50 mL) and hydrazine monohydrate (1.1 mL) were added to the reaction mixture, and the mixture was treated in the same manner as in Example 1(3) to give a crude product of methyl 3-ethyl-1H-pyrazole-4-carboxylate. This was dissolved in dimethylformamide (30 ml), potassium carbonate (4.2 g) and 2-chloro-5-trifluoromethylpyridine (3.6 g) were added, and the mixture was stirred at 100° C. for 2 hr. In the same manner as in Example 1(4), the title object compound (4.7 g, 79%) was obtained as a yellow solid.

Provenance & Evidence