Water → 7-Chloro-2-(3-methyl-2-furyl)pyrazolo[1,5-a]pyridine-3-carbaldehyde

HRID 1269066Notes

Reaction equation

HRID 1269066 reaction equation
CN(C)[CH:3]=[O:4].P(Cl)(Cl)(Cl)=O.[Cl:11][C:12]1[N:17]2[N:18]=[C:19]([C:21]3[O:22][CH:23]=[CH:24][C:25]=3[CH3:26])[CH:20]=[C:16]2[CH:15]=[CH:14][CH:13]=1.O>ClCCl>[Cl:11][C:12]1[N:17]2[N:18]=[C:19]([C:21]3[O:22][CH:23]=[CH:24][C:25]=3[CH3:26])[C:20]([CH:3]=[O:4])=[C:16]2[CH:15]=[CH:14][CH:13]=1

Participants

6

Reactant 4

HCID 962WaterHCID 6228DimethylformamideHCID 24813Phosphorus oxychlorideHCID 184466337-Chloro-2-(3-methyl-2-furyl)pyrazolo[1,5-a]pyridine

Product 1

HCID 184466327-Chloro-2-(3-methyl-2-furyl)pyrazolo[1,5-a]pyridine-3-carbaldehydeYield 760%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

A dry flask charged with dry N,N-dimethylformamide (100 mL) was treated with phosphorous oxychloride (8.8 mL, 94 mmol). The resultant solution was stirred at room temperature for 1 hour. 7-Chloro-2-(3-methyl-2-furyl)pyrazolo[1,5-a]pyridine (14.6 g, 63 mmol) was added and the reaction mixture was stirred for 2.5 hours. Water and dichloromethane were added to quench the reaction. The aqueous phase and organic phase were separated. The aqueous phase was extracted with dichloromethane. The organics were combined and washed with water, dried over magnesium sulfate, filtered and the filtrate was concentrated. Crystallization from a small amount of methanol gave 7-chloro-2-(3-methyl-2-furyl)pyrazolo[1,5-a]pyridine-3-carbaldehyde (12.4 g, 760%) as a peach color crystalline compound. 1H NMR (CDCl3): δ 10.58 (s, 1H), 8.43 (d, 1H), 7.58 (d, 1H), 7.48 (t, 1H), 7.21 (d, 1H), 6.51 (d, 1H), 2.56 (s, 3H). MS m/261 (M+1).

Workup

  1. customto quench
  2. customthe reaction
  3. customThe aqueous phase and organic phase were separated
  4. extractionThe aqueous phase was extracted with dichloromethane
  5. washwashed with water
  6. dry with materialdried over magnesium sulfate
  7. filtrationfiltered
  8. concentrationthe filtrate was concentrated
  9. customCrystallization from a small amount of methanol

Sources & evidence

ORD record
ord-dc06c0c05c054162845f4f9f0c79fec4
Source dataset
uspto-grants-2007_04
Patent number
US07199120B2

Reaction notes

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