Реакция #792151

Уравнение реакции

N,N-dimethylformamide

1-phenyl-3-(trifluoromethyl)pyrazole-5-carboxylic acid

product

1-Phenyl-3-(trifluoromethyl)-1H-pyrazole-5-carboxylic acid

oxalyl chloride

→

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

Растворители

methylene chloride

Условия реакции

Обработка

1. 1
   Температураwas heated
2. 2
   Температураto reflux for a period of 35 minutes
3. 3
   ДругоеVolatiles were removed
4. 4
   Другоеon a rotary evaporator at a bath temperature of 55° C

Методика

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.

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