تفاعل #1221

معادلة التفاعل

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

المذيبات

THF

ظروف التفاعل

المعالجة

1. 1
   workup.ADDITIONOnce the addition
2. 2
   درجة الحرارةthe mixture was heated
3. 3
   درجة الحرارةat reflux for one hour
4. 4
   درجة الحرارةthe 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
   استخلاصextracted with ethyl ether
8. 8
   أخرىthe organic phase decanted off
9. 9
   تجفيفdried over magnesium sulfate
10. 10
    أخرىevaporated
11. 11
    أخرىThe residue obtained
12. 12
    أخرىwas chromatographed on a silica column
13. 13
    غسيلeluted with a mixture of hexane and dichloromethane (60/40)
14. 14
    أخرىAfter evaporation of the solvents, 6.35 g (74%) of the expected ester of melting point 107°-108° C.
15. 15
    أخرىwere recovered

الإجراء التجريبي

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.

المصدر