Hydrochloric Acid → 4-(Ethoxycarbonyl)-1-methyl-1H-pyrazole-5-carboxylic acid

HRID 1958320Notes

Reaction equation

HRID 1958320 reaction equation
C([O:3][C:4]([C:6]1[N:7]([CH3:16])[N:8]=[CH:9][C:10]=1[C:11]([O:13][CH2:14][CH3:15])=[O:12])=[O:5])C.[OH-].[Na+].Cl>>[CH2:14]([O:13][C:11]([C:10]1[CH:9]=[N:8][N:7]([CH3:16])[C:6]=1[C:4]([OH:5])=[O:3])=[O:12])[CH3:15]

Participants

4

Reactant 3

HCID 313Hydrochloric AcidHCID 14798Sodium Hydroxide2×HCID 670417284,5-Diethyl 1-methyl-1H-pyrazole-4,5-dicarboxylate

Product 1

HCID 252475674-(Ethoxycarbonyl)-1-methyl-1H-pyrazole-5-carboxylic acid

Procedure

(This compound was prepared in close analogy to the method of Perez et al., Spanish patent appl. ES 493459.) 2-Methyl-2H-pyrazole-3,4-dicarboxylic acid diethyl ester (2.06 g, 9.1 mmol) was suspended in a NaOH solution (0.5M in water, 20 ml, 10 mmol) and heated to reflux (30 min). If the conversion was incomplete after this time, as indicated by HPLC control, small amounts of NaOH were added in 30 min intervals. The reaction mixture was cooled, and HCl was added, and stirred for an additional 30 min (r.t.). The precipitate was filtered, washed (water, small amount) and dried under vacuum. The title compound was obtained as a white solid (1.27 g, 70%), and was used in the next step without further purification. MS (m/e)=198 [M+H+].

Workup

  1. custom(This compound was prepared in close analogy to the method of Perez et al., Spanish patent appl
  2. temperatureheated
  3. temperatureto reflux (30 min)
  4. additionwere added in 30 min intervals
  5. temperatureThe reaction mixture was cooled
  6. filtrationThe precipitate was filtered
  7. washwashed (water, small amount)
  8. customdried under vacuum

Sources & evidence

ORD record
ord-ce7149d26046438085304710fc08bf36
Source dataset
uspto-grants-2013_04
Patent number
US08410117B2

Reaction notes

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