Ammonia → HCID 13604324, compound

HRID 1982483Notes

Reaction equation

HRID 1982483 reaction equation
[CH3:1][O:2][C:3]1[CH:7]=[C:6]([S:8][CH3:9])[S:5][C:4]=1[C:10](O)=O.[NH2:13][C:14]1[C:19]([NH2:20])=[CH:18][CH:17]=[CH:16][N:15]=1.O.N>P(Cl)(Cl)(Cl)=O.CO>[CH3:1][O:2][C:3]1[CH:7]=[C:6]([S:8][CH3:9])[S:5][C:4]=1[C:10]1[NH:20][C:19]2[C:14]([N:13]=1)=[N:15][CH:16]=[CH:17][CH:18]=2

Participants

7

Reactant 4

HCID 222AmmoniaHCID 962Water2×HCID 99562,3-Diaminopyridine2×HCID 10965623HCID 10965623, compound

Product 1

HCID 13604324HCID 13604324, compound

Reagents, catalysts & solvents 2

HCID 887MethanolSolventHCID 24813Phosphorus oxychlorideSolvent

Procedure

6.83 g (33.4 mmoles) of 3-methoxy-5-methylthio-2-thiophene carboxylic acid (formula (II): R=CH3, R2 =SCH3) are refluxed together with 3.65 g (33.4 mmoles) of 2,3-diaminopyridine (formula III): R1 =H) in 80 ml of phosphorous oxychloride for 3 hours. The reaction mixture obtained is then introduced in portions into about 1.5 l of cold water, stirred well, filtered over Hyflo, made alkaline with potassium carbonate and some ammonia, and extracted several times with methylene chloride. The combined organic phases are dried over sodium sulfate and evaporated. The dark residue is suspended in about 300 ml of methanol, an excess of methanolic hydrochloric acid is added, heated to boiling, activated charcoal is added, filtered, and the solution is concentrated to about 100 ml and allowed to cool. A yellow hydrochloride precipitate of (I) is removed by suction and washed with a small amount of methanol. For preparing the free base, these crystals are suspended in 28 ml of methanol, 1.2 g of a 25% aqueous solution of ammonia are added, 80 ml of water are added, and the yellow crystalline precipitate is removed by suction, washed with water and dried. Yield: 4.24 g (46%), m.p. (ethanol) 224° C. (dec.).

Workup

  1. customThe reaction mixture obtained
  2. filtrationfiltered over Hyflo
  3. extractionsome ammonia, and extracted several times with methylene chloride
  4. dry with materialThe combined organic phases are dried over sodium sulfate
  5. customevaporated
  6. additionan excess of methanolic hydrochloric acid is added
  7. temperatureheated
  8. additionactivated charcoal is added
  9. filtrationfiltered
  10. concentrationthe solution is concentrated to about 100 ml
  11. temperatureto cool
  12. customA yellow hydrochloride precipitate of (I) is removed by suction
  13. washwashed with a small amount of methanol
  14. customFor preparing the free base
  15. customthe yellow crystalline precipitate is removed by suction
  16. washwashed with water
  17. customdried

Sources & evidence

ORD record
ord-6a3bafd8bcbe4a98a46ba29b2034b261
Source dataset
uspto-grants-1986_06
Patent number
US04596830

Reaction notes

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