Bromine → 6-Bromo-5-methyl-2,3-dihydro-1,4-benzodioxine

HRID 1768664Notes

Reaction equation

HRID 1768664 reaction equation
[CH3:1][C:2]1[C:11]2[O:10][CH2:9][CH2:8][O:7][C:6]=2[CH:5]=[CH:4][CH:3]=1.[Br:12]Br.S([O-])(O)=O.[Na+]>C(O)(=O)C>[Br:12][C:3]1[CH:4]=[CH:5][C:6]2[O:7][CH2:8][CH2:9][O:10][C:11]=2[C:2]=1[CH3:1]

Participants

5

Reactant 3

HCID 24408BromineHCID 122388275-Methyl-1,4-benzodioxaneHCID 23665763Sodium Bisulfite

Product 1

HCID 124645276-Bromo-5-methyl-2,3-dihydro-1,4-benzodioxineYield 98.3%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

In 30 ml of acetic acid, was dissolved 10 g of 5-methyl-1,4-benzodioxane and 11.8 g of bromine was added dropwise to the solution. After stirring for 30 minutes, the reaction mixture was poured into a sodium hydrogen sulfite aqueous solution and extracted with diethyl ether. The resulting diethyl ether layer was washed successively with a sodium hydrogen carbonate aqueous solution, water and saturated saline solution, dried over anhydrous magnesium sulfate, and the solvent was removed under reduced pressure to obtain 15.0 g of 6-bromo-5-methyl-l,4benzodioxane (bp. 126°-135° C. (7 mmHg)). 1H-NMR (CDC13) δ(ppm): 2.25 (3H, s), 4.23 (4H, s), 6.60 (1H, d, J=8.9Hz), 6.99 (1H, d, J=8.9Hz).

Workup

  1. additionwas added dropwise to the solution
  2. extractionextracted with diethyl ether
  3. washThe resulting diethyl ether layer was washed successively with a sodium hydrogen carbonate aqueous solution, water and saturated saline solution
  4. dry with materialdried over anhydrous magnesium sulfate
  5. customthe solvent was removed under reduced pressure

Sources & evidence

ORD record
ord-0c0bfd8168a74c7d95b39b2ab39403a6
Source dataset
uspto-grants-1995_01
Patent number
US05378726

Reaction notes

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