Dipropylamine → 2-(5-Methyl-2-thienyl)-N,N-dipropyl-3H-imidazo[4,5-b]pyridine-3-acetamide

HRID 622034Notes

Reaction equation

HRID 622034 reaction equation
[CH3:1][C:2]1[S:6][C:5]([C:7]2[N:15]([CH2:16][C:17]([OH:19])=O)[C:10]3=[N:11][CH:12]=[CH:13][CH:14]=[C:9]3[N:8]=2)=[CH:4][CH:3]=1.C(N1C=CN=C1)(N1C=CN=C1)=O.[CH2:32]([NH:35][CH2:36][CH2:37][CH3:38])[CH2:33][CH3:34]>O1CCCC1.C(O)(C)C>[CH3:1][C:2]1[S:6][C:5]([C:7]2[N:15]([CH2:16][C:17]([N:35]([CH2:36][CH2:37][CH3:38])[CH2:32][CH2:33][CH3:34])=[O:19])[C:10]3=[N:11][CH:12]=[CH:13][CH:14]=[C:9]3[N:8]=2)=[CH:4][CH:3]=1

Participants

6

Reactant 3

HCID 8902DipropylamineHCID 682631,1'-CarbonyldiimidazoleHCID 156171962-(5-methyl-2-thienyl)-3H-imidazo[4,5-b]pyridine-3-acetic acid

Product 1

HCID 143903932-(5-Methyl-2-thienyl)-N,N-dipropyl-3H-imidazo[4,5-b]pyridine-3-acetamideYield 35%

Reagents, catalysts & solvents 2

HCID 3776IsopropanolSolventHCID 8028TetrahydrofuranSolvent2×

Procedure

A solution of 2-(5-methyl-2-thienyl)-3H-imidazo[4,5-b]pyridine-3-acetic acid (5.0 g, 0.0183 mole) and 1,1'-carbonyldiimidazole (2.97 g, 0.0183 mole) in tetrahydrofuran (100 ml) was stirred at room temperature for 3 hours with a stream of nitrogen bubbling through it. A solution of dipropylamine (5.56 g, 0.055 mole) in tetrahydrofuran (7 ml) was added and the reaction mixture was stirred overnight at room temperature. The solvents were evaporated and the residue was partitioned between water and ethyl acetate. The layers were separated and the aqueous layer was extracted again with ethyl acetate. The combined organic layer was washed twice with water, twice with a 5% potassium hydroxide solution, and twice again with water. The organic layer was dried over magnesium sulfate, treated with charcoal, filtered, and evaporated to give a solid which was dissolved in hot isopropyl alcohol and filtered while hot. Addition of water and cooling caused a solid to precipitate. The solid was dissolved again in hot isopropyl alcohol with charcoal, filtered while hot and brought to the cloud point by addition of water. Upon cooling, solid precipitated which was collected by filtration, rinsed with water, and dried under high vacuum at 50° C. overnight to give 2.28 g (35%) of title compound, mp 125°-127° C.

Workup

  1. customThe solvents were evaporated
  2. customthe residue was partitioned between water and ethyl acetate
  3. customThe layers were separated
  4. extractionthe aqueous layer was extracted again with ethyl acetate
  5. washThe combined organic layer was washed twice with water, twice with a 5% potassium hydroxide solution
  6. dry with materialThe organic layer was dried over magnesium sulfate
  7. additiontreated with charcoal
  8. filtrationfiltered
  9. customevaporated
  10. customto give a solid which
  11. filtrationfiltered while hot
  12. additionAddition of water
  13. temperaturecooling
  14. customto precipitate
  15. dissolutionThe solid was dissolved again in hot isopropyl alcohol with charcoal
  16. filtrationfiltered while hot and
  17. additionbrought to the cloud point by addition of water
  18. temperatureUpon cooling
  19. customsolid precipitated which
  20. filtrationwas collected by filtration
  21. washrinsed with water
  22. customdried under high vacuum at 50° C. overnight

Sources & evidence

ORD record
ord-82e5931aa1d149a7b89761981e78740a
Source dataset
uspto-grants-1989_04
Patent number
US04824951

Reaction notes

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