Ethyl 3-(N,N-dimethylamino)acrylate → Ethyl 3-(2-phenylpyrazolo[1,5-a]pyridin-3-yl)acrylate

HRID 981956Notes

Reaction equation

HRID 981956 reaction equation
[Cl-].[Al+3].[Cl-].[Cl-].[C:5]1([C:11]2[CH:19]=[C:14]3[CH:15]=[CH:16][CH:17]=[CH:18][N:13]3[N:12]=2)[CH:10]=[CH:9][CH:8]=[CH:7][CH:6]=1.CN(C)[CH:22]=[CH:23][C:24]([O:26][CH2:27][CH3:28])=[O:25].C(=O)(O)[O-].[Na+]>C(Cl)Cl>[C:5]1([C:11]2[C:19]([CH:22]=[CH:23][C:24]([O:26][CH2:27][CH3:28])=[O:25])=[C:14]3[CH:15]=[CH:16][CH:17]=[CH:18][N:13]3[N:12]=2)[CH:6]=[CH:7][CH:8]=[CH:9][CH:10]=1

Participants

6

Reactant 4

HCID 121015Ethyl 3-(N,N-dimethylamino)acrylateHCID 516892Sodium BicarbonateHCID 6451240Aluminum(III) ChlorideHCID 156203422-Phenylpyrazolo[1,5-a]pyridine

Product 1

HCID 53784179Ethyl 3-(2-phenylpyrazolo[1,5-a]pyridin-3-yl)acrylateYield 86.8%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

Aluminum chloride (298 mg) was added portionwise to a solution of 2-phenylpyrazolo[1,5-a]pyridine (145 mg) and ethyl 3-dimethylaminoacrylate (316 mg) in methylene chloride (2 ml) at 5° to 6° C. After being stirred at room temperature overnight, the reaction mixture was poured onto water (50 ml), neutralized with saturated aqueous sodium bicarbonate solution, and extracted with chloroform (50 ml ×2). The extracts were washed with saturated sodium chloride aqueous solution (20 ml), dried over magnesium sulfate, and evaporated in vacuo. The residue was chromatographed on silica gel with a mixture of chloroform and n-hexane (1:1) as an eluent. The fractions containing the objective compound were combined and evaporated in vacuo to give ethyl 3-(2-phenylpyrazolo[1,5-a]pyridin -3-yl)acrylate (trans isomer) (189.4 mg).

Workup

  1. additionthe reaction mixture was poured onto water (50 ml)
  2. extractionextracted with chloroform (50 ml ×2)
  3. washThe extracts were washed with saturated sodium chloride aqueous solution (20 ml)
  4. dry with materialdried over magnesium sulfate
  5. customevaporated in vacuo
  6. customThe residue was chromatographed on silica gel with a mixture of chloroform and n-hexane (1:1) as an eluent
  7. additionThe fractions containing the objective compound
  8. customevaporated in vacuo

Sources & evidence

ORD record
ord-8c9ce1fa52cc4474b24f24aa33c414ef
Source dataset
uspto-grants-1991_02
Patent number
US04994453

Reaction notes

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