p-Toluenesulfonic acid → 2-[(6-bromohexyl)oxy]tetrahydro-2H-pyran

HRID 658975Notes

Reaction equation

HRID 658975 reaction equation
[Br:1][CH:2](O)[CH2:3][CH2:4][CH2:5][CH2:6]C.CC1C=CC(S(O)(=O)=O)=CC=1.[O:20]1[CH:25]=[CH:24][CH2:23][CH2:22][CH2:21]1.[C:26]([O-:29])(O)=O.[Na+]>CC(OC)(C)C>[Br:1][CH2:2][CH2:3][CH2:4][CH2:5][CH2:6][CH2:26][O:29][CH:25]1[CH2:24][CH2:23][CH2:22][CH2:21][O:20]1

Participants

6

Reactant 4

HCID 6101p-Toluenesulfonic acidHCID 80803,4-dihydro-2H-pyranHCID 516892Sodium BicarbonateHCID 21981760Bromohexanol

Product 1

HCID 1038602-[(6-bromohexyl)oxy]tetrahydro-2H-pyranYield 90%

Reagents, catalysts & solvents 1

HCID 15413tert-Butyl methyl etherSolvent

Conditions

Temperature
2.5 °C

Procedure

Bromohexanol (54.67 g) is dissolved in TBME (250 mL) and dried over Na2SO4. After filtration, TsOH (0.6 mmol) is added and the solution is cooled in an ice bath. 3,4-Dihydropyran (394 mmol) is added dropwise, while maintaining the temperature around 2-3° C. After complete addition the reaction mixture is allowed to reach ambient temperature overnight. The mixture is ished with sat. NaHCO3 (2×200 mL). The aqueous layer is extracted with TBME (200 mL) and the combined organic layers are ished with brine (200 mL). After drying over Na2SO4 (containing some K2CO3), the solvent is evaporated to yield (XX) as a colourless oil (90%), which is stored at 4° C. over K2CO3 and is used without further purification.

Workup

  1. dry with materialdried over Na2SO4
  2. additionis added
  3. temperaturethe solution is cooled in an ice bath
  4. additionAfter complete addition the reaction mixture
  5. extractionThe aqueous layer is extracted with TBME (200 mL)
  6. dry with materialAfter drying over Na2SO4 (
  7. additioncontaining some K2CO3), the solvent
  8. customis evaporated

Sources & evidence

ORD record
ord-afe048c966604aa4a34bbb32b427196b
Source dataset
uspto-grants-2011_12
Patent number
US08080540B2

Reaction notes

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