Dimethylformamide → HCID 18983806, compound

HRID 1440468Notes

Reaction equation

HRID 1440468 reaction equation
Br.[C:2]1([C:8]2[N:9]=[C:10]3[C:15]([C:16]([O:18][CH2:19][CH3:20])=[O:17])=[CH:14][CH:13]=[CH:12][N:11]3[CH:21]=2)[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.P(Cl)(Cl)(Cl)=O.[OH-].[Na+].CN([CH:32]=[O:33])C>>[CH:32]([C:21]1[N:11]2[CH:12]=[CH:13][CH:14]=[C:15]([C:16]([O:18][CH2:19][CH3:20])=[O:17])[C:10]2=[N:9][C:8]=1[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1)=[O:33]

Participants

5

Reactant 4

HCID 6228DimethylformamideHCID 14798Sodium HydroxideHCID 24813Phosphorus oxychlorideHCID 67768891Ethyl 2-phenyl-imidazo[1,2-a]pyridine-8-carboxylate hydrogen bromide

Product 1

HCID 18983806HCID 18983806, compoundYield 85.5%

Procedure

To a solution of ethyl 2-phenyl-imidazo[1,2-a]-pyridine-8-carboxylate hydrogen bromide (14.7 g, 4 m mol) in DMF (8 ml) was dropwise added phosphorus oxychloride (2 ml) keeping the inner temperature to below 15° C. Then, the mixture was allowed to react at room temperature for 30 minutes and at 70° C. for 2 hours. After completion of the reaction, the reaction mixture was cooled, poured into ice water and adjusted to pH 7 by adding 20% sodium hydroxide. The precipitated crystals were collected by filtration and recrystallized from ethanol to obtain the object compound (1.0 g, yield 85.5%) as colorless crystals. m.p. 139° C.

Workup

  1. customto below 15° C
  2. customto react at room temperature for 30 minutes and at 70° C. for 2 hours
  3. customAfter completion of the reaction
  4. temperaturethe reaction mixture was cooled
  5. filtrationThe precipitated crystals were collected by filtration
  6. customrecrystallized from ethanol

Sources & evidence

ORD record
ord-a62180c8cd4040f98372e34a881adb56
Source dataset
uspto-grants-1996_03
Patent number
US05498774

Reaction notes

Loading…