Dimethylformamide → 1-Phenyl-3-(trifluoromethyl)-1H-pyrazole-5-carbonyl chloride

HRID 641996Notes

Reaction equation

HRID 641996 reaction equation
[C:1]1([N:7]2[C:11]([C:12](O)=[O:13])=[CH:10][C:9]([C:15]([F:18])([F:17])[F:16])=[N:8]2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.C(Cl)(=O)C([Cl:22])=O.CN(C)C=O>C(Cl)Cl.CN(C)C=O>[C:1]1([N:7]2[C:11]([C:12]([Cl:22])=[O:13])=[CH:10][C:9]([C:15]([F:18])([F:17])[F:16])=[N:8]2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1

Participants

6

Reactant 3

HCID 6228DimethylformamideHCID 65578Oxalyl chlorideHCID 222503231-Phenyl-3-(trifluoromethyl)-1H-pyrazole-5-carboxylic acid2×

Product 1

HCID 222503331-Phenyl-3-(trifluoromethyl)-1H-pyrazole-5-carbonyl chloride

Reagents, catalysts & solvents 2

HCID 6228DimethylformamideCatalystHCID 6344DichloromethaneSolvent

Procedure

A sample of crude 1-phenyl-3-(trifluoromethyl)pyrazole-5-carboxylic acid (i.e. the product of Step B) (4.13 g, 16.1 mmol) was dissolved in methylene chloride (45 mL). The solution was treated with oxalyl chloride (1.80 mL, 20.6 mmol), followed by N,N-dimethylformamide (0.010 mL, 0.13 mmol). Off-gassing began shortly after adding the N,N-dimethylformamide catalyst. The reaction mixture was stirred for ˜20 minutes under ambient conditions, then was heated to reflux for a period of 35 minutes. Volatiles were removed by stripping the reaction mixture on a rotary evaporator at a bath temperature of 55° C. The product consisted of 4.43 g of a light-yellow oil. The only impurity observed by 1H NMR was N,N-dimethylformamide.

Workup

  1. temperaturewas heated
  2. temperatureto reflux for a period of 35 minutes
  3. customVolatiles were removed
  4. customon a rotary evaporator at a bath temperature of 55° C

Sources & evidence

ORD record
ord-284d67d6a75b41ea80a0e3f0fb8b34c3
Source dataset
uspto-grants-2010_04
Patent number
US07696232B2

Reaction notes

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