Ethanol → 1-(6-Chloro-2-pyrazinyl)-4,5-dihydro-5-methyl-1H-pyrazol-3-amine

HRID 1731659Notes

Reaction equation

HRID 1731659 reaction equation
[Na].C(O)C.[Cl:5][C:6]1[CH:11]=[N:10][CH:9]=[C:8]([NH:12][NH2:13])[N:7]=1.[C:14](#[N:18])/[CH:15]=[CH:16]/[CH3:17]>C1C=CC=CC=1>[NH2:18][C:14]1[CH2:15][CH:16]([CH3:17])[N:12]([C:8]2[CH:9]=[N:10][CH:11]=[C:6]([Cl:5])[N:7]=2)[N:13]=1

Participants

6

Reactant 4

HCID 702EthanolHCID 637921CrotononitrileHCID 5360545SodiumHCID 126931852-Chloro-6-hydrazinylpyrazine

Product 1

HCID 202281821-(6-Chloro-2-pyrazinyl)-4,5-dihydro-5-methyl-1H-pyrazol-3-amine

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Procedure

A 0.30 g. amount of sodium metal is dissolved in 100 ml. of absolute ethanol, then 6.72 g. of 2-chloro-6-hydrazinopyrazine (prepared as described above) is added and after 5 minutes, 4.6 g. of distilled crotononitrile is added. The reaction mixture is refluxed for 6 hours. The solvent is removed in vacuo and water is added to the residue to separate a gum. The gum is dissolved in dichloromethane, dried over magnesium sulfate and filtered. The filtrate is evaporated to give a gum. The gum is treated with benzene to separate yellow crystals. The crystals are collected, dried and recrystallized from acetone-hexane to give 1.4 g of the desired product as yellow crystals, m.p. 147°-148° C.

Workup

  1. temperatureThe reaction mixture is refluxed for 6 hours
  2. customThe solvent is removed in vacuo and water
  3. additionis added to the residue
  4. customto separate a gum
  5. dissolutionThe gum is dissolved in dichloromethane
  6. dry with materialdried over magnesium sulfate
  7. filtrationfiltered
  8. customThe filtrate is evaporated
  9. customto give a gum
  10. customto separate yellow crystals
  11. customThe crystals are collected
  12. customdried
  13. customrecrystallized from acetone-hexane

Sources & evidence

ORD record
ord-24bace7734ec424abb0bc091444b3d16
Source dataset
uspto-grants-1986_11
Patent number
US04622401

Reaction notes

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