Реакция #1221

Уравнение реакции

5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-bromoanthracene

magnesium

ethyl 2-bromo-4-thiophenecarboxylate

→

ethyl 2-(5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-anthryl)-4-thiophenecarboxylate

Растворители

THF

Условия реакции

Обработка

1. 1
   workup.ADDITIONOnce the addition
2. 2
   Температураthe mixture was heated
3. 3
   Температураat reflux for one hour
4. 4
   Температураthe mixture was maintained
5. 5
   workup.STIRRINGunder stirring at room temperature for 12 hours
6. 6
   workup.ADDITIONThe reaction medium was poured into ice-cold water
7. 7
   Экстракцияextracted with ethyl ether
8. 8
   Другоеthe organic phase decanted off
9. 9
   Сушкаdried over magnesium sulfate
10. 10
    Другоеevaporated
11. 11
    ДругоеThe residue obtained
12. 12
    Другоеwas chromatographed on a silica column
13. 13
    Промывкаeluted with a mixture of hexane and dichloromethane (60/40)
14. 14
    ДругоеAfter evaporation of the solvents, 6.35 g (74%) of the expected ester of melting point 107°-108° C.
15. 15
    Другоеwere recovered

Методика

A solution of 9.5 g (30 mmol) of 5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-bromoanthracene was added dropwise to a suspension of 724 mg (30 mmol) of magnesium in 10 ml of THF. Once the addition was completed, the mixture was heated at reflux for one hour. At room temperature 4.1 g (30 mmol) of anhydrous zinc chloride were added and the mixture was stirred for one hour. 5.2 g (22 mmol) of ethyl 2-bromo-4-thiophenecarboxylate and 120 mg (0.22 mmol) of the complex NiCl2 /DPPE were then added successively and the mixture was maintained under stirring at room temperature for 12 hours. The reaction medium was poured into ice-cold water, extracted with ethyl ether, the organic phase decanted off, dried over magnesium sulfate and evaporated. The residue obtained was chromatographed on a silica column eluted with a mixture of hexane and dichloromethane (60/40). After evaporation of the solvents, 6.35 g (74%) of the expected ester of melting point 107°-108° C. were recovered.

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