Benzyl Bromide → Ethyl 3,5-dibenzyloxyphenylacetate

HRID 2253731Notes

Reaction equation

HRID 2253731 reaction equation
[OH:1][C:2]1[CH:3]=[C:4]([CH2:9][C:10]([O:12][CH2:13][CH3:14])=[O:11])[CH:5]=[C:6]([OH:8])[CH:7]=1.[CH2:15](Br)[C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1.C([O-])([O-])=O.[K+].[K+]>CC(C)=O>[CH2:15]([O:1][C:2]1[CH:3]=[C:4]([CH2:9][C:10]([O:12][CH2:13][CH3:14])=[O:11])[CH:5]=[C:6]([O:8][CH2:9][C:4]2[CH:5]=[CH:6][CH:7]=[CH:2][CH:3]=2)[CH:7]=1)[C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1

Participants

5

Reactant 3

HCID 7498Benzyl BromideHCID 11430Potassium CarbonateHCID 579799Ethyl 2-(3,5-dihydroxyphenyl)acetate

Product 1

HCID 563149Ethyl 3,5-dibenzyloxyphenylacetate

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

A solution of ethyl 3,5-dihydroxyphenylacetate (4.0 g, 20.39 mmol), benzyl bromide (4.85 ml, 6.97 g, 40.77 mmol, 2 eq) and 5.64 g (40.77 mmol, 2 eq) of K2CO3 in 100 ml of acetone is refluxed overnight. The mixture is concentrated in vacuo, then partitioned between EtOAc and H2O. The organics are dried (MgSO4) and concentrated in vacuo. This is then passed through a flash silica gel column that is slurry packed with hexanes and eluted with 10% EtOAc in hexanes. Concentration of desired fractions gives ethyl 3,5-dibenzyloxyphenylacetate which is confirmed by NMR and used directly in the next step.

Workup

  1. concentrationThe mixture is concentrated in vacuo
  2. custompartitioned between EtOAc and H2O
  3. dry with materialThe organics are dried (MgSO4)
  4. concentrationconcentrated in vacuo
  5. washeluted with 10% EtOAc in hexanes

Sources & evidence

ORD record
ord-19c519ce63d04f7a88402dc9d7e8da5f
Source dataset
uspto-grants-1993_08
Patent number
US05232948

Reaction notes

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