HCID 22388428, compound → 219761-99-6

HRID 1072781Notes

Reaction equation

HRID 1072781 reaction equation
[CH3:1][C:2]1[C:13](C(O)=O)=[C:5]2[CH:6]=[C:7]([C:10]([OH:12])=[O:11])[CH:8]=[CH:9][N:4]2[N:3]=1>ClCCl.CO.O>[CH3:1][C:2]1[CH:13]=[C:5]2[CH:6]=[C:7]([C:10]([OH:12])=[O:11])[CH:8]=[CH:9][N:4]2[N:3]=1

Participants

4

Reactant 1

HCID 22388428HCID 22388428, compound

Product 1

HCID 22388435219761-99-6Yield 54.8%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 21226129Dichloromethane methanolSolvent

Conditions

Temperature
150 °C

Procedure

A mixture of 2-methylpyrazolo[1,5-a]pyridine-3,5-dicarboxylic acid (1.39 g) and polyphosphoric acid (13.9 g) was stirred at 150° C. with heating for 2 hr, and ice (14 g) was added under ice-cooling, which was followed by shaking to give a homogeneous solution. The reaction mixture was adjusted to pH 4 at the same temperature and diluted with dichloromethane/methanol (4:1) and water. The precipitate was collected by filtration to give the objective compound (610 mg) as a pale-brown powder. The organic layer of the mother liquor was taken, and the aqueous layer was extracted with dichloromethane/methanol (4:1). Both organic layers were combined, dried over magnesium sulfate and concentrated to dryness under reduced pressure. The residue was washed with ether to give second crystals (200 mg) as a pale-brown powder.

Workup

  1. temperaturewith heating for 2 hr
  2. temperaturecooling
  3. stirringby shaking
  4. customto give a homogeneous solution
  5. filtrationThe precipitate was collected by filtration

Sources & evidence

ORD record
ord-630156b5afb24617988105fe39f5d225
Source dataset
uspto-grants-2005_06
Patent number
US06911469B2

Reaction notes

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