Ethylene Glycol → 2-(6-Bromonaphthalen-2-yl)-2-methyl-1,3-dioxolane

HRID 35190Notes

Reaction equation

HRID 35190 reaction equation
[Br:1][C:2]1[CH:11]=[CH:10][C:9]2[C:4](=[CH:5][CH:6]=[C:7]([C:12](=[O:14])[CH3:13])[CH:8]=2)[CH:3]=1.[CH2:15](O)[CH2:16][OH:17].[OH-].[Na+]>C1(C)C=CC(S(O)(=O)=O)=CC=1.C1C=CC=CC=1>[Br:1][C:2]1[CH:11]=[CH:10][C:9]2[C:4](=[CH:5][CH:6]=[C:7]([C:12]3([CH3:13])[O:17][CH2:16][CH2:15][O:14]3)[CH:8]=2)[CH:3]=1

Participants

6

Reactant 3

HCID 174Ethylene GlycolHCID 14798Sodium HydroxideHCID 124330821-(6-Bromonaphthalen-2-yl)ethanone

Product 1

HCID 136879082-(6-Bromonaphthalen-2-yl)-2-methyl-1,3-dioxolaneYield 79.7%

Reagents, catalysts & solvents 2

HCID 6101p-Toluenesulfonic acidCatalystHCID 241BenzeneSolvent

Procedure

A mixture of 13.0 g of 2-bromo-6-acetylnaphthalene, 20 g of ethylene glycol, 200 ml of benzene, and 530 mg of p-toluenesulfonic acid was heated at reflux for 18 hours using a Dean-Stark trap to effect continuous removal of water. The cooled reaction mixture was added to 100 ml of 0.1N sodium hydroxide solution and the resulting mixture extracted with three 75 ml portions of diethyl ether. The combined organic extract was washed with 100 ml saturated sodium chloride solution and then dried over sodium sulfate. The solvent is removed under vacuum and the residue recrystallized from hexane to give 12.2 g of 2-bromo-6-(2-methyl-1,3-dioxolan-2-yl)naphthalene, m.p. 80°-82° C.

Workup

  1. temperaturewas heated
  2. temperatureat reflux for 18 hours
  3. customremoval of water
  4. customThe cooled reaction mixture
  5. extractionthe resulting mixture extracted with three 75 ml portions of diethyl ether
  6. extractionThe combined organic extract
  7. washwas washed with 100 ml saturated sodium chloride solution
  8. dry with materialdried over sodium sulfate
  9. customThe solvent is removed under vacuum
  10. customthe residue recrystallized from hexane

Sources & evidence

ORD record
ord-7b120238d0e6436e8080b71c290403cf
Source dataset
uspto-grants-1988_08
Patent number
US04766127

Reaction notes

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