Hydrochloric Acid → 1-Ethyl-3-(pentafluoroethyl)-4-(trifluoromethyl)-1H-pyrazole-5-carboxylic acid

HRID 1843071Notes

Reaction equation

HRID 1843071 reaction equation
[F:1][C:2]([F:20])([C:7]1[C:11]([C:12]([F:15])([F:14])[F:13])=[C:10]([C:16]([O:18]C)=[O:17])[NH:9][N:8]=1)[C:3]([F:6])([F:5])[F:4].C(=O)([O-])[O-].[K+].[K+].I[CH2:28][CH3:29].[OH-].[Na+].Cl>CC(C)=O.O>[CH2:28]([N:9]1[C:10]([C:16]([OH:18])=[O:17])=[C:11]([C:12]([F:14])([F:15])[F:13])[C:7]([C:2]([F:1])([F:20])[C:3]([F:5])([F:6])[F:4])=[N:8]1)[CH3:29]

Participants

8

Procedure

0.23 g (0.72 mmol) of methyl 3-(pentafluoroethyl)-4-(trifluoromethyl)-1H-pyrazole-5-carboxylate and 0.3 g (2.2 mmol) of potassium carbonate are suspended in 7.0 ml of acetone and admixed with 0.12 ml of iodoethane (1.4 mmol). The reaction mixture is stirred overnight at room temperature. 1.1 ml (2.2 mmol) of 2N sodium hydroxide solution are added to the suspension. The solution is then stirred overnight at room temperature. The reaction mixture is diluted with water and adjusted to pH 2-3 with 1M hydrochloric acid. The aqueous reaction solution is extracted three times with ethyl acetate. The combined organic phases are dried over magnesium sulphate, filtered and concentrated by evaporation under reduced pressure on a rotary evaporator. This gives 0.22 g of 1-ethyl-3-(pentafluoroethyl)-4-(trifluoromethyl)-1H-pyrazole-5-carboxylic acid (91%) as a colourless solid.

Workup

  1. stirringThe solution is then stirred overnight at room temperature
  2. extractionThe aqueous reaction solution is extracted three times with ethyl acetate
  3. dry with materialThe combined organic phases are dried over magnesium sulphate
  4. filtrationfiltered
  5. concentrationconcentrated by evaporation under reduced pressure on a rotary evaporator

Sources & evidence

ORD record
ord-9c85271981d1488c92b3975492eb27aa
Source dataset
uspto-grants-2015_02
Patent number
US08946234B2

Reaction notes

Loading…