Dimethylformamide → 3-(Benzyloxy)-4-bromophenol

HRID 1660077Notes

Reaction equation

HRID 1660077 reaction equation
[H-].[K+].CN(C)C=O.[Br:8][C:9]1[CH:15]=[CH:14][C:12]([OH:13])=[CH:11][C:10]=1[OH:16].[CH2:17](Br)[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1>CCOCC.O>[CH2:17]([O:16][C:10]1[CH:11]=[C:12]([OH:13])[CH:14]=[CH:15][C:9]=1[Br:8])[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1

Participants

7

Reactant 4

HCID 6228DimethylformamideHCID 7498Benzyl BromideHCID 811054-BromoresorcinolHCID 82127Potassium hydride

Product 1

HCID 156706543-(Benzyloxy)-4-bromophenol

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 3283Diethyl EtherSolvent

Conditions

Temperature
0 °C

Procedure

To a 0° C. slurry of 1.7 g. (42.5 mmoles) of potassium hydride in 35 ml. of N,N-dimethylformamide was slowly added a solution of 7.22 g. (38.2 mmoles) of 4-bromoresorcinol. The resultant mixture was stirred for 30 minutes and then 4.54 ml. (38.2 mmoles) of benzyl bromide was slowly added. The reaction mixture was stirred 3 hours longer at 0° C. and then added to 200 ml. of cold water and 200 ml. of ether. The ether extract was washed twice with 200 ml. portions of water, dried over magnesium sulfate and evaporated to an oil. The crude oil was purified via column chromatography on 400 g. of silica gel eluted with 25% ether-pentane to yield (in order of elution) 2.2 g. (16%) of 2,4-dibenzyloxybromobenzene, 0.21 g. (2%) of 5-benzyloxy-2-bromophenol and 3.52 g. (33%) of 3-benzyloxy-4-bromophenol.

Workup

  1. customTo a 0° C.
  2. additionadded to 200 ml
  3. extractionThe ether extract
  4. washwas washed twice with 200 ml
  5. dry with materialportions of water, dried over magnesium sulfate
  6. customevaporated to an oil
  7. customThe crude oil was purified via column chromatography on 400 g
  8. washof silica gel eluted with 25% ether-pentane
  9. customto yield
  10. wash(in order of elution) 2.2 g

Sources & evidence

ORD record
ord-52d8d5c8f3cb40d5bcadfa6c967c5814
Source dataset
uspto-grants-1981_12
Patent number
US04306097

Reaction notes

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