Hydrochloric Acid → 4-(3,4-Dimethoxyphenyl)-1H-pyrrole-3-carbonitrile

HRID 2118832Notes

Reaction equation

HRID 2118832 reaction equation
[OH-].[K+].[C:3]([C:5](=[CH:9][C:10]1[CH:15]=CC(OC)=[C:12](OC)[CH:11]=1)[C:6](O)=O)#[N:4].S([CH2:30][N+:31]#[C-])(C1C=CC(C)=CC=1)(=O)=O.Cl.[CH2:34]([CH2:37][O:38][CH3:39])[O:35][CH3:36]>O>[CH3:36][O:35][C:34]1[CH:15]=[C:10]([C:9]2[C:5]([C:3]#[N:4])=[CH:6][NH:31][CH:30]=2)[CH:11]=[CH:12][C:37]=1[O:38][CH3:39]

Participants

7

Reactant 5

HCID 313Hydrochloric AcidHCID 80711,2-Dimethoxyethane2×HCID 14797Potassium HydroxideHCID 161915Tosylmethyl isocyanideHCID 6162612-Cyano-3-(3,4-dimethoxyphenyl)prop-2-enoic acid

Product 1

HCID 136318574-(3,4-Dimethoxyphenyl)-1H-pyrrole-3-carbonitrileYield 92%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

12.62 g (225.0 m mol) of potassium hydroxide was added to 100 ml of dimethoxyethane. The solution was then cooled at a temperature from 0° C. to 10° C., was fed with 11.66 g (50.0 m mol) of alpha-cyano-3,4-dimethoxycinnamic acid, and was stirred for 30 min. at the same temperature. The liquid was then fed dropwise for one hour, at room temperature, with a solution of 10.25 g (52.5 m mol) of tosyl methylisocyanide in 60 ml of dimethoxyethane. When the dropping ended, the mixed liquid was stirred for two hours at room temperature till the reaction completed. Then, to the reaction mixture 70 ml of water was added and neutralized to pH 8 by 10% HCl. From the neutralized mixture, dimethoxyethane was distilled off under reduced pressure, then 800 ml of water was further added thereto, and the mixture was stirred for 30 min. to precipitate crystals. The crystals were then filtered off and washed with water and dried. As the result, 10.50 g of 3-(3,4-dimethoxyphenyl)-4-cyanopyrrole was obtained. Yield 92.0%, Melting point 212°-214° C.

Workup

  1. temperatureThe solution was then cooled at a temperature from 0° C. to 10° C.
  2. stirringthe mixed liquid was stirred for two hours at room temperature till the reaction
  3. distillationFrom the neutralized mixture, dimethoxyethane was distilled off under reduced pressure
  4. addition800 ml of water was further added
  5. stirringthe mixture was stirred for 30 min.
  6. customto precipitate crystals
  7. filtrationThe crystals were then filtered off
  8. washwashed with water
  9. customdried

Sources & evidence

ORD record
ord-584764f4eea6475c98cc638f326036c0
Source dataset
uspto-grants-1987_07
Patent number
US04680413

Reaction notes

Loading…