2-Bromopropane → HCID 13961712, compound

HRID 256342Notes

Reaction equation

HRID 256342 reaction equation
[CH3:1][C:2](C)([O-])[CH3:3].[K+].[OH:7][C:8]1[C:12]2[CH:13]=[C:14]([O:17][CH3:18])[CH:15]=[CH:16][C:11]=2[O:10][C:9]=1[C:19]([O:21][CH3:22])=[O:20].BrC(C)C>CS(C)=O>[CH3:22][O:21][C:19]([C:9]1[O:10][C:11]2[CH:16]=[CH:15][C:14]([O:17][CH3:18])=[CH:13][C:12]=2[C:8]=1[O:7][CH:2]([CH3:3])[CH3:1])=[O:20]

Participants

5

Reactant 3

HCID 63582-BromopropaneHCID 23665647Potassium tert-butoxideHCID 54732577Methyl 3-hydroxy-5-methoxy-1-benzofuran-2-carboxylate

Product 1

HCID 13961712HCID 13961712, compoundYield 46%

Reagents, catalysts & solvents 1

HCID 679Dimethyl SulfoxideSolvent

Procedure

A solution of 12.3g (0.11 mole) of potassium tert-butoxide in 100 ml of dimethyl sulfoxide (under a nitrogen atmosphere) is cooled in a cold water bath and treated dropwise with a solution of 16.6 g (0.075 mole) of 3-hydroxy-5-methoxy-2-benzofuran carboxylic acid, methyl ester. The mixture is stirred for 45 minutes after completion of the addition, and 7.0 ml (9.2 g; 0.075 mole) of 2-bromopropane is added in one portion. After stirring for 24 hours at room temperature, the reaction mixture is added to 1.5 kg of ice/water and stirred an additional hour. The precipitated product is filtered and washed with water. The crude yield is 9.0 g (46% yield). A sample recrystallized from aqueous methanol yields analytically pure 5-methoxy-3-(1-methylethoxy)-2-benzofurancarboxylic acid methyl ester, mp 66°-68° C.

Workup

  1. additionis added in one portion
  2. stirringAfter stirring for 24 hours at room temperature
  3. stirringstirred an additional hour
  4. filtrationThe precipitated product is filtered
  5. washwashed with water
  6. customA sample recrystallized from aqueous methanol

Sources & evidence

ORD record
ord-2434a4950101458e86dc2c04d3a1cd19
Source dataset
uspto-grants-1987_10
Patent number
US04703053

Reaction notes

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