Butanal → 2-Propyl-4,7-dimethyl-4,7-dihydro-1,3-dioxepin

HRID 34429Notes

Reaction equation

HRID 34429 reaction equation
[CH3:1][CH:2]([OH:8])[CH:3]=[CH:4][CH:5]([OH:7])[CH3:6].[CH:9](=O)[CH2:10][CH2:11][CH3:12].C1(C)C=CC=CC=1>C1(C)C=CC(S(O)(=O)=O)=CC=1.O>[CH2:10]([CH:9]1[O:8][CH:2]([CH3:1])[CH:3]=[CH:4][CH:5]([CH3:6])[O:7]1)[CH2:11][CH3:12]

Participants

6

Reactant 3

HCID 261ButanalHCID 1140TolueneHCID 2469903-Hexen-2,5-diol

Product 1

HCID 212847012-Propyl-4,7-dimethyl-4,7-dihydro-1,3-dioxepinYield 80%

Reagents, catalysts & solvents 2

HCID 6101p-Toluenesulfonic acidCatalystHCID 962WaterSolvent

Procedure

A mixture of 580 g (5 moles) of hex-3-ene-2,5-diol, 3 g of p-toluenesulfonic acid, 360 g (5 moles) of n-butanal and 1 l of toluene was refluxed, and the resulting water of reaction (108 ml) was removed in the course of 3 h. Thereafter, the mixture was left to cool to room temperature, 10 ml of a 25% strength aqueous sodium hydroxide solution were added, the mixture was washed neutral with a little water and the toluene was removed under reduced pressure at from 50° to 60° C. The residue obtained was distilled under 0.1 mbar to give 681 g (4 moles) of 2-propyl-4,7-dimethyl-4,7-dihydro-1,3-dioxepin of boiling point 70° C./0.1 mbar.

Workup

  1. temperaturewas refluxed
  2. customwas removed in the course of 3 h
  3. waitThereafter, the mixture was left
  4. addition10 ml of a 25% strength aqueous sodium hydroxide solution were added
  5. washthe mixture was washed neutral with a little water
  6. customthe toluene was removed under reduced pressure at from 50° to 60° C
  7. customThe residue obtained
  8. distillationwas distilled under 0.1 mbar

Sources & evidence

ORD record
ord-3cc14764d9214dbe927a098e5c6244cc
Source dataset
uspto-grants-1988_08
Patent number
US04761489

Reaction notes

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