Hydrazine hydrate (1:1) → HCID 23333669, compound

HRID 904122Notes

Reaction equation

HRID 904122 reaction equation
[C:1]([CH:9]([CH3:15])[CH:10]([CH3:14])[C:11](O)=[O:12])(=O)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.O.[NH2:17][NH2:18]>C(O)C>[CH3:14][CH:10]1[CH:9]([CH3:15])[C:1]([C:2]2[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=2)=[N:18][NH:17][C:11]1=[O:12]

Participants

4

Reactant 2

HCID 24654Hydrazine hydrate (1:1)HCID 12240573HCID 12240573, compound

Product 1

HCID 23333669HCID 23333669, compound

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A 200 g. portion of 3-benzoyl-2,3-dimethyl-propionic acid and 60 g. of hydrazine hydrate are added to one liter of ethyl alcohol and stirred at reflux for 18 hours. The reaction mixture is then cooled in an ice bath and collected in a conventional manner to afford 4,5-dihydro-4,5-dimethyl-6-phenyl-3(2H)-pyridazinone as a cream colored solid. This product is partially dissolved in 600 ml. of glacial acetic acid. To this is added, portionwise, a solution of 50 ml. of bromine in 100 ml. of glacial acetic acid, while warming on a steam bath (approximately 15% of the bromine solution is added to the reaction mixture before warming is started and about one hour is required to complete the addition during which time quantities of hydrogen bromide gas are given off). After the addition is completed, the reaction mixture is heated on the steam bath for one hour, and then the mixture is poured onto crushed ice. The resulting solid is vacuum filtered, washed copiously with water, and air dried to give 4,5-dimethyl-6 -phenyl-3(2H)-pyridazinone as a cream colored solid. This material is added to 800 ml. of phosphorus oxychloride and is heated on a steam bath for 5 hours. The reaction mixture is concentrated to remove the excess phosphorus oxychloride and is then diluted with cold water. The resulting solid is vacuum filtered, washed copiously with water, and air dried to give 3-chloro-4,5-dimethyl-6-phenylpyridazine as a pinkish solid. A 10 g. portion of this product plus 8 g. of N-acetylhydrazine and 100 ml. of n-butyl alcohol is allowed to stir at reflux for 48 hours. The reaction mixture is cooled in an ice bath and the resulting solid is vacuum filtered, washed first with petroleum ether and then with water, and is air dried. The solid is recrystallized from ethyl alcohol after treatment with activated charcoal and is dried in vacuo to give 3,7,8-trimethyl-6-phenyl-1,2,4-triazolo[4,3-b]pyridazine as a white solid.

Workup

  1. temperatureat reflux for 18 hours
  2. temperatureThe reaction mixture is then cooled in an ice bath
  3. customcollected in a conventional manner

Sources & evidence

ORD record
ord-2249e9fcb0f244b5b6cacfd6bc74a76c
Source dataset
uspto-grants-1980_10
Patent number
US04230705

Reaction notes

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