Hydrochloric Acid → 2-Acetylamino-3-cyano-4-ethoxy-5-formylthiophene

HRID 1591294Notes

Reaction equation

HRID 1591294 reaction equation
[C:1]([NH:4][C:5]1[S:6][CH:7]=[C:8]([O:12][CH2:13][CH3:14])[C:9]=1[C:10]#[N:11])(=[O:3])[CH3:2].P(Cl)(Cl)(Cl)=O.[OH-].[Na+].Cl.CN(C)[CH:25]=[O:26]>>[C:1]([NH:4][C:5]1[S:6][C:7]([CH:25]=[O:26])=[C:8]([O:12][CH2:13][CH3:14])[C:9]=1[C:10]#[N:11])(=[O:3])[CH3:2]

Participants

6

Procedure

210 parts of 2-acetylamino-3-cyano-4-ethoxythiophene (Example 7) are introduced into 1000 parts of dimethylformamide, and 200 parts of phosphoryl trichloride are added dropwise in the course of 4 hours. Stirring is continued for 4 hours at 60° C., after which the resulting crystal slurry is brought into solution by adding 600 parts of ice. This solution is stirred into 2000 parts of 12.5% strength sodium hydroxide solution, and acidified with hydrochloric acid after 6 hours. The precipitated product is filtered off under suction, washed with water and dried to give 201 parts of 2-acetylamino-3-cyano-4-ethoxy-5-formylthiophene. A sample recrystallized from dimethylformamide has a melting point of 276°-277° C. and possesses the following analytical values:

Workup

  1. additionare added dropwise in the course of 4 hours
  2. additionby adding 600 parts of ice
  3. filtrationThe precipitated product is filtered off under suction
  4. washwashed with water
  5. customdried

Sources & evidence

ORD record
ord-21c93ae11f2549cca6aab3c039bcf60f
Source dataset
uspto-grants-1993_04
Patent number
US05206375

Reaction notes

Loading…