Hydrogen Peroxide → 2,2-Difluoro-1-benzyloxy-5-hydroxypentane

HRID 568977Notes

Reaction equation

HRID 568977 reaction equation
[F:1][C:2]([F:15])([CH2:12][CH:13]=[CH2:14])[CH2:3][O:4][CH2:5][C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1.[BH4-].[Na+].[OH-:18].[Na+].OO>O1CCCC1.CCOCC.[Cl-].[Na+].O.O>[F:1][C:2]([F:15])([CH2:12][CH2:13][CH2:14][OH:18])[CH2:3][O:4][CH2:5][C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1

Participants

9

Reactant 4

HCID 784Hydrogen PeroxideHCID 14798Sodium HydroxideHCID 4311764Sodium borohydrideHCID 201494522,2-Difluoro-1-benzyloxy-4-pentene

Product 1

HCID 201494602,2-Difluoro-1-benzyloxy-5-hydroxypentaneYield 54%

Reagents, catalysts & solvents 4

HCID 962WaterSolventHCID 3283Diethyl EtherSolventHCID 8028TetrahydrofuranSolventHCID 57417360Sodium chloride; waterSolvent

Procedure

To a mixture of (29) (16.8 g, 79 mmoles) and sodium borohydride (901 mg, 23.7 mmoles, 20% excess) in dry tetrahydrofuran (75 ml), kept under nitrogen at room temperature, borontrifluoride-ether complex (4.07 ml, 31.6 mmoles, 20% excess) is added over a period of 25 min. After standing for 13/4 hours at room temperature, the reaction mixture is slowly hydrolyzed with water (6 ml). Addition of 3N NaOH (10 ml) is followed by careful introduction of hydrogen peroxide (10 ml, 30%) at such a rate that the internal temperature does not exceed 40° C. The temperature is then allowed to return to room temperature, and the reaction mixture is diluted with ether and brine. Usual work-up affords a mixture of isomeric alcohols (17.2 g) which is separated by chromatography on silica (ethyl acetate/petroleum ether: 15/85, RF: 0.1) to give 9.8 g (54%) of the title compound.

Workup

  1. customkept under nitrogen at room temperature
  2. additionborontrifluoride-ether complex (4.07 ml, 31.6 mmoles, 20% excess) is added over a period of 25 min
  3. custom4 hours
  4. customat room temperature
  5. customdoes not exceed 40° C
  6. customto return to room temperature
  7. customUsual work-up affords
  8. customis separated by chromatography on silica (ethyl acetate/petroleum ether: 15/85, RF: 0.1)

Sources & evidence

ORD record
ord-860128155fe54dfc8a5669a6bf3523ad
Source dataset
uspto-grants-1988_03
Patent number
US04730006

Reaction notes

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