Реакция #2254188

Уравнение реакции

ethylcyanoformate

Ethylmagnesium chloride

3-(5-bromo-4-methyl-thiophen-2-yl)-5-(3,5-dichloro-phenyl)-5-trifluoromethyl-4,5-dihydro-isoxazole

→

5-[5-(3,5-dichloro-phenyl)-5-trifluoromethyl-4,5-dihydro-isoxazol-3-yl]-3-methyl-thiophene-2-carboxylic acid ethyl ester

Выход 56.8%

Растворители

THF

THF

Условия реакции

Обработка

1. 1
   workup.WAITAfter 40 minutes
2. 2
   Другоеthe reaction is quenched with a saturated aqueous solution of NH4Cl in water
3. 3
   ЭкстракцияThe mixture is extracted three times with MTBE
4. 4
   Сушкаdried over Na2SO4
5. 5
   Концентрированиеconcentrated in vacuo
6. 6
   ДругоеThe crude product is purified on a semi-preparative HPLC

Методика

Ethylmagnesium chloride (10.9 ml, 2M in THF) is added over 30 minutes to a solution of 3-(5-bromo-4-methyl-thiophen-2-yl)-5-(3,5-dichloro-phenyl)-5-trifluoromethyl-4,5-dihydro-isoxazole (10.0 g, Example 2, step D) in THF (15 ml) at 0° C. After 1 hour at room temperature, a solution of ethylcyanoformate (2.81 g) in THF (15 ml) is added to the reaction mixture. After 40 minutes, the reaction is quenched with a saturated aqueous solution of NH4Cl in water. The mixture is extracted three times with MTBE. The organic phases are combined, dried over Na2SO4 and concentrated in vacuo. The crude product is purified on a semi-preparative HPLC to yield 5-[5-(3,5-dichloro-phenyl)-5-trifluoromethyl-4,5-dihydro-isoxazol-3-yl]-3-methyl-thiophene-2-carboxylic acid ethyl ester (5.6 g) as a yellowish oil.

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