Dichloromethane → 2-(4-Hydroxyphenyl)-5-pentylthiophene

HRID 2121297Notes

Reaction equation

HRID 2121297 reaction equation
B(Br)(Br)Br.ClCCl.C[O:9][C:10]1[CH:15]=[CH:14][C:13]([C:16]2[S:17][C:18]([CH2:21][CH2:22][CH2:23][CH2:24][CH3:25])=[CH:19][CH:20]=2)=[CH:12][CH:11]=1>O>[OH:9][C:10]1[CH:15]=[CH:14][C:13]([C:16]2[S:17][C:18]([CH2:21][CH2:22][CH2:23][CH2:24][CH3:25])=[CH:19][CH:20]=2)=[CH:12][CH:11]=1

Participants

5

Reactant 3

HCID 6344Dichloromethane2×HCID 25134Boron tribromideHCID 234321132-(4-Methoxyphenyl)-5-pentylthiophene

Product 1

HCID 234323142-(4-Hydroxyphenyl)-5-pentylthiopheneYield 81.4%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

A solution of boron tribromide (3.2 cm3) and dichloromethane (30 cm3) was added dropwise to a solution of 2-(4-methoxyphenyl)-5-pentylthiophene (10.0 g) and dichloromethane (70 cm3) at 0° C. under an atmosphere of nitrogen. The reaction solution was stirred overnight at room temperature and water (100 cm3) added. The organic layer was separated off and the aqueous layer extracted with dichloromethane (2×100 cm3). The combined organic layers were washed with brine (2×100 cm3) and then dried (MgSO4), filtered and evaporated down. The residue was purified by column chromatography on silica gel using a 4:1 hexane/dichloromethane mixture as eluent and recrystallisation from hexane to yield 7.7 g of g 2-(4-hydroxyphenyl)-5-pentylthiophene, K 100-102° C., I.

Workup

  1. customThe organic layer was separated off
  2. extractionthe aqueous layer extracted with dichloromethane (2×100 cm3)
  3. washThe combined organic layers were washed with brine (2×100 cm3)
  4. dry with materialdried (MgSO4)
  5. filtrationfiltered
  6. customevaporated down
  7. customThe residue was purified by column chromatography on silica gel using a 4:1 hexane/dichloromethane mixture as eluent
  8. customrecrystallisation from hexane

Sources & evidence

ORD record
ord-16905664bdd644e98b28daabbe53758f
Source dataset
uspto-grants-2004_02
Patent number
US06696110B1

Reaction notes

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