Реакция #792162

Уравнение реакции

potassium carbonate

2,3-dichloropyridine

3-chloropyrazole

product

3-Chloropyrazole

→

title product

3-Chloro-2-(3-chloro-1H-pyrazol-1-yl)pyridine

Растворители

N,N-dimethylformamide

Условия реакции

Обработка

1. 1
   ТемператураThe reaction mixture was cooled to room temperature
2. 2
   ФильтрацияThe precipitated solids were filtered
3. 3
   Промывкаwashed with water
4. 4
   ФильтрацияThe solid filter cake
5. 5
   Сушкаdried over magnesium sulfate
6. 6
   Концентрированиеconcentrated
7. 7
   ДругоеThe crude solid was chromatographed on silica gel using 20% ethyl acetate/hexane as eluent

Методика

To a mixture of 2,3-dichloropyridine (92.60 g, 0.629 mol) and 3-chloropyrazole (i.e. the product of Step B) (64.44 g, 0.629 mol) in N,N-dimethylformamide (400 mL) was added potassium carbonate (147.78 g, 1.06 mol), and the reaction mixture was then heated to 100° C. for 36 hours. The reaction mixture was cooled to room temperature and slowly poured into ice water. The precipitated solids were filtered and washed with water. The solid filter cake was taken up in ethyl acetate, dried over magnesium sulfate and concentrated. The crude solid was chromatographed on silica gel using 20% ethyl acetate/hexane as eluent to afford the title product as a white solid (39.75 g).

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