3-Methyl-2-buten-1-OL → Chromanol

HRID 653830Notes

Reaction equation

HRID 653830 reaction equation
[CH3:1][C:2]1[C:8]([CH3:9])=[C:7]([OH:10])[CH:6]=[C:5]([CH3:11])[C:3]=1[OH:4].[Cl-].[Al+3].[Cl-].[Cl-].[CH3:16][C:17]([CH3:21])=[CH:18][CH2:19]O>ClCCl>[CH3:16][C:17]1([CH3:21])[CH2:18][CH2:19][C:6]2[C:7](=[C:8]([CH3:9])[C:2]([CH3:1])=[C:3]([OH:4])[C:5]=2[CH3:11])[O:10]1

Participants

5

Reactant 3

HCID 111733-Methyl-2-buten-1-OLHCID 12785TrimethylhydroquinoneHCID 6451240Aluminum(III) Chloride

Product 1

HCID 99479ChromanolYield 41.2%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

257 g (1.69 mol) of 2,3,6-trimethylhydroquinone were introduced into a suspension of 248 g (1.86 mol) of anhydrous aluminum chloride in 850 ml of dry dichloromethane at 5° C. After stirring for 30 min, 160 g (1.86 mol) of 3-methyl-2-buten-1-ol were added dropwise at 5°-10° C. The mixture was stirred at room temperature overnight and then poured into ice-water, the precipitate was filtered off, the filtrate was extracted with dichloromethane, and the organic phase was washed with water to neutrality, dried over magnesium sulfate and evaporated. Distillation of the residue provided a main fraction of 153.3 g of the title compound at 140° C. and 0.4 mbar, and this was recrystallized from heptane with a melting point of 85°-88° C.

Workup

  1. stirringThe mixture was stirred at room temperature overnight
  2. filtrationthe precipitate was filtered off
  3. extractionthe filtrate was extracted with dichloromethane
  4. washthe organic phase was washed with water to neutrality
  5. dry with materialdried over magnesium sulfate
  6. customevaporated
  7. distillationDistillation of the residue

Sources & evidence

ORD record
ord-72c4f110757a457fb017fbca0e3fd78f
Source dataset
uspto-grants-1992_07
Patent number
US05128479

Reaction notes

Loading…