تفاعل #43408

معادلة التفاعل

1,1-dimethylethyl [2-chloro-5-fluoro-6-(methyloxy)-3-pyridinyl]carbamate

caesium fluoride

tributyl[1-(ethyloxy)ethenyl]stannane

potassium fluoride

→

1,1-Dimethylethyl [2-[1-(ethyloxy)ethenyl]-5-fluoro-6-(methyloxy)-3-pyridinyl]carbamate

المذيبات

1,4-dioxane

ظروف التفاعل

المعالجة

1. 1
   ترشيحthe mixture was filtered through Kieselguhr
2. 2
   غسيلwashing with 1,4-dioxane
3. 3
   workup.ADDITIONEthyl acetate and water were added to the filtrate
4. 4
   أخرىThe phases were separated
5. 5
   استخلاصthe aqueous phase extracted twice with ethyl acetate
6. 6
   تجفيفThe combined organic extracts were dried over magnesium sulphate
7. 7
   أخرىevaporated
8. 8
   أخرىThe residue was rapidly chromatographed
9. 9
   غسيلeluting with 25-50% dichloromethane in hexane affording the product as a light brown oil (22.2 g, 99%)

الإجراء التجريبي

A degassed solution of 1,1-dimethylethyl [2-chloro-5-fluoro-6-(methyloxy)-3-pyridinyl]carbamate (20 g, 72.2 mmol) in 1,4-dioxane (200 ml) was treated with bis(tri-tert-butylphosphine) palladium(0) (1.05 g), caesium fluoride (21.93 g) and tributyl[1-(ethyloxy)ethenyl]stannane (26.9 ml) then heated to 100° C. overnight. The cooled mixture was treated with 10% aqueous potassium fluoride solution. After 0.5 hour stirring, the mixture was filtered through Kieselguhr, washing with 1,4-dioxane. Ethyl acetate and water were added to the filtrate. The phases were separated and the aqueous phase extracted twice with ethyl acetate. The combined organic extracts were dried over magnesium sulphate and evaporated. The residue was rapidly chromatographed eluting with 25-50% dichloromethane in hexane affording the product as a light brown oil (22.2 g, 99%).

المصدر