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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1484507Generated: October 25, 2026

Hydrochloric Acid → 4-(4-bromophenyl)-3-methyl-4,5-dihydro-1H-1,2,4-triazol-5-one

https://huagongshe.com/reaction/1484507

Reaction equation

Participants

RoleNameHCIDCharge
ReactantHydrochloric AcidHCID 313—
ReactantSodium HydroxideHCID 14798—
Reactant2-acetyl-N-(4-bromophenyl)hydrazinecarboxamideHCID 23274183—
SolventWaterHCID 962—
Product4-(4-bromophenyl)-3-methyl-4,5-dihydro-1H-1,2,4-triazol-5-oneHCID 1487791—

Reaction Conditions

Temperature130 °C

Reaction Steps

A large microwave tube was filled in with 2-acetyl-N-(4-bromophenyl)hydrazinecarboxamide (1.8 g, 6.62 mmol) and 2M aqueous NaOH (9 mL, 18 mmol). The reaction mixture was heated under microwave irradiation for 20 min at 130° C. Water (ca 18 mL) was added and the pH was adjusted to 4 by dropwise addition of aqueous HCl, with stirring. The thick precipitate was collected by filtration, washed with small amounts of cold water and dried. A small amount (220 mg) was purified by analytical preparation leading to 195 mg of the title compound.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS09422252B2
Source datasetuspto-grants-2016_08
ORD IDord-ed06d3196331403db184342ecda5e251
Source noteuspto-grants-2016_08