Hydrochloric Acid → HCID 17978859, compound

Participants

Reaction Steps

17.4 g (92 mmol) of 5-amino-1-(4-methoxyphenyl)pyrazole [sic] from Step 1.1 was dissolved in 200 mL of tetrahydrofuran, 52.4 g of 32% hydrochloric acid was added, and the mixture was cooled to 0–5° C. Then 11.8 g (101 mmol) of isopentyl nitrite was added dropwise with agitation so that the temperature did not exceed 5° C. Gradually, a brownish precipitate formed which after an additional 2-hour agitation period in an ice bath was removed by suction filtration and washed with a small amount of tetrahydrofuran. Drying gave 16.4 g (64 mmol, 70% of the theoretical) of 5-amino-1-(4-methoxyphenyl)-4-nitrosopyrazole hydrochloride.

Provenance & Evidence