반응 #361688

반응 방정식

boron tribromide

hexyl (3-cyano-4,5-dimethoxyphenyl)glyoxylate

methanol

→

methyl (3-cyano-4,5-dihydroxyphenyl)glyoxylate

용매

methylene chloride

methylene chloride

반응 조건

후처리

1. 1
   workup.ADDITIONare added dropwise
2. 2
   workup.STIRRINGat -60° , the mixture is stirred at room temperature for 1 hour
3. 3
   기타evaporated
4. 4
   온도It is heated
5. 5
   온도under reflux for 10 minutes
6. 6
   기타evaporated to dryness
7. 7
   기타dried in a high vacuum
8. 8
   기타The thus-obtained crude product
9. 9
   기타is recrystallized from acetonitrile

실험 절차

4.8 ml of boron tribromide dissolved in 20 ml of methylene chloride are added dropwise while cooling with ice within 20 minutes to 4.0 g of hexyl (3-cyano-4,5-dimethoxyphenyl)glyoxylate dissolved in 100 ml of methylene chloride and the reaction mixture is stirred at room temperature for 18 hours. 40 ml of methanol are subsequently added dropwise thereto at -60° , the mixture is stirred at room temperature for 1 hour and evaporated. The residue is taken up in methanol. It is heated under reflux for 10 minutes, evaporated to dryness and dried in a high vacuum. The thus-obtained crude product is recrystallized from acetonitrile. There is obtained methyl (3-cyano-4,5-dihydroxyphenyl)glyoxylate of m.p. 252°.

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