p-Toluenesulfonic acid → HCID 69328147, compound

HRID 1754562Notes

Reaction equation

HRID 1754562 reaction equation
[NH:1]1[CH:5]=[C:4]([C:6]([OH:8])=[O:7])[CH:3]=[N:2]1.C1(C)C=CC(S(O)(=O)=O)=CC=1.[CH2:20]1[CH2:25][O:24][CH:23]=[CH:22][CH2:21]1.C([O-])(O)=O.[Na+]>CN(C=O)C>[O:24]1[CH2:25][CH2:20][CH2:21][CH2:22][CH:23]1[N:1]1[CH:5]=[C:4]([C:6]([OH:8])=[O:7])[CH:3]=[N:2]1

Participants

6

Reactant 4

HCID 6101p-Toluenesulfonic acidHCID 80803,4-dihydro-2H-pyranHCID 516892Sodium BicarbonateHCID 3015937Pyrazole-4-carboxylic acid

Product 1

HCID 69328147HCID 69328147, compoundYield 70%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

To a suspension of 1H-pyrazole-4-carboxylic acid (50 g, 446 mmol) in 500 mL of DMF are added para-toluenesulfonic acid (8.48 g, 44 mmol) and DHP (132 mL, 1561 mmol). The reaction medium turns yellow and then black after stirring at room temperature for 20 hours. The reaction mixture is poured into saturated aqueous NaHCO3 solution and extracted with EtOAc. The aqueous phase is acidified to pH 3 by adding 6M hydrochloric acid solution. The precipitate formed is filtered off and washed with water and then dried under vacuum at 50° C. to give 61.2 g of a white powder (yield: 70%).

Workup

  1. extractionextracted with EtOAc
  2. additionby adding 6M hydrochloric acid solution
  3. customThe precipitate formed
  4. filtrationis filtered off
  5. washwashed with water
  6. customdried under vacuum at 50° C.

Sources & evidence

ORD record
ord-0e1c9c45acb743c7a4cb1c5c3580f81d
Source dataset
uspto-grants-2015_10
Patent number
US09169246B2

Reaction notes

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