Ethyl propiolate → HCID 178422434, compound

HRID 1636183Notes

Reaction equation

HRID 1636183 reaction equation
CC(C)([O-])C.[K+].[Br:7][C:8]1[CH:13]=[CH:12][C:11]([NH:14][NH2:15])=[C:10]([CH3:16])[CH:9]=1.[C:17](OCC)(=[O:20])[C:18]#[CH:19]>O>[Br:7][C:8]1[CH:13]=[CH:12][C:11]([N:14]2[CH:19]=[CH:18][C:17]([OH:20])=[N:15]2)=[C:10]([CH3:16])[CH:9]=1

Participants

5

Reactant 3

HCID 12182Ethyl propiolateHCID 3722075(4-bromo-2-methylphenyl)hydrazineHCID 23665647Potassium tert-butoxide

Product 1

HCID 178422434HCID 178422434, compoundYield 24.3%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

Potassium tert-butoxide (20 ml, 1M in tert-butanol, 20.0 mmol) was added to 1-(4-bromo-2-methylphenyl)hydrazine (J. Chem. Soc. 109; 1916; 582)(2.01 g, 10.0 mmol) to give a dark brown suspension. Ethyl propiolate (1.02 ml, 10 mmol) was then added dropwise over 10 minutes, with cooling, and once addition was complete, the reaction was heated under reflux for 4 hours. The reaction was diluted with water (200 ml) and this mixture washed with dichloromethane (2×50 ml). The aqueous phase was acidified using hydrochloric acid (2N), extracted with dichloromethane (5×100 ml), these combined organic extracts dried (MgSO4), filtered and evaporated in vacuo. The crude product was purified by column chromatography on silica gel using dichloromethane:methanol (98:2) as eluant, and triturated with ether/di-isopropyl ether to give the title compound (615 mg, 24%) as a solid.

Workup

  1. customto give a dark brown suspension
  2. temperaturewith cooling
  3. additiononce addition
  4. temperaturethe reaction was heated
  5. temperatureunder reflux for 4 hours
  6. washthis mixture washed with dichloromethane (2×50 ml)
  7. extractionextracted with dichloromethane (5×100 ml)
  8. dry with materialthese combined organic extracts dried (MgSO4)
  9. filtrationfiltered
  10. customevaporated in vacuo
  11. customThe crude product was purified by column chromatography on silica gel
  12. customtriturated with ether/di-isopropyl ether

Sources & evidence

ORD record
ord-76741dea1c454254ab7659e8e08b8fd9
Source dataset
uspto-grants-2003_01
Patent number
US06511993B1

Reaction notes

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