Water → (4-Methylbenzo[b]thiophen-3-yl)methanol

HRID 1835959Notes

Reaction equation

HRID 1835959 reaction equation
Br[C:2]1[C:7]2[S:8][CH:9]=[C:10]([CH2:11][OH:12])[C:6]=2[C:5]([CH3:13])=[CH:4][CH:3]=1.C1(C)C=CC=CC=1.C(OCC)(=O)C.O>C1(C)C=CC=CC=1.C1COCC1>[OH:12][CH2:11][C:10]1[C:6]2[C:5]([CH3:13])=[CH:4][CH:3]=[CH:2][C:7]=2[S:8][CH:9]=1

Participants

6

Reactant 4

HCID 962Water2×HCID 1140TolueneHCID 8857Ethyl Acetate2×HCID 98137867-Bromo-3-hydroxymethyl-4-methyl-benzo[b]thiophene

Product 1

HCID 11148058(4-Methylbenzo[b]thiophen-3-yl)methanolYield 97%

Reagents, catalysts & solvents 1

HCID 22635083Tetrahydrofuran tolueneSolvent

Conditions

Temperature
70 °C

Procedure

A solution of 7-bromo-3-hydroxymethyl-4-methyl-benzo[b]thiophene (45.91 g, 179 mmol) in toluene-THF (5/1, 220 ml) was placed in an ice bath, to which a solution of 3.4 M sodium hydrogenated bis(2-methoxyethoxy)aluminum in toluene (215 ml, 731 mmol) was added dropwise over 30 minutes. After the dropwise addition was complete, the reaction mixture was stirred at 70° C. for 3 hours, and it was brought back to room temperature and placed in an ice bath, to which ethyl acetate (300 ml) was slowly added dropwise. After stirring in the ice bath for 5 minutes, water (600 ml) was slowly added dropwise. The internal temperature increased from 17° C. to 35° C. To the reaction mixture, 1 L of water and 500 ml of ethyl acetate were added, and extracted. The aqueous phase was further extracted with 300 ml of ethyl acetate, and the combined organic phase was washed with water (300 ml×6 times). After drying the organic phase on magnesium sulfate, the solvent was evaporated to obtain pale orange crude crystals 3-hydroxymethyl-4-methyl-benzo[b]thiophene (30.80 g, 173 mmol). The yield was 97%.

Workup

  1. additionAfter the dropwise addition
  2. customwas brought back to room temperature
  3. additionwas slowly added dropwise
  4. temperatureThe internal temperature increased from 17° C. to 35° C
  5. extractionextracted
  6. extractionThe aqueous phase was further extracted with 300 ml of ethyl acetate
  7. washthe combined organic phase was washed with water (300 ml×6 times)
  8. customAfter drying the organic phase on magnesium sulfate
  9. customthe solvent was evaporated

Sources & evidence

ORD record
ord-6e4cc2bc21204b468363f0ea83237754
Source dataset
uspto-grants-2004_08
Patent number
US06774245B2

Reaction notes

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