Reaction #571556

Reaction equation

HCl

phenol

2,2,5,5-tetramethyltetrahydrofuran

aluminum chloride

→

title compound

5,5,8,8-Tetramethyl-5,6,7,8-tetrahydro-2-naphthol

Solvents

heptane

Conditions

Workup

1. 1
   workup.ADDITIONAfter the addition
2. 2
   Temperatureat reflux for 2 hours
3. 3
   workup.WAITat room temperature for a further 16 hours
4. 4
   workup.STIRRINGstirred for 0.5 hours
5. 5
   FiltrationThe mixture was filtered
6. 6
   Washthe residue washed with water
7. 7
   Otherdried in-vacuo
8. 8
   Otherto give crude product
9. 9
   OtherThe organic layer was separated from the filtrate
10. 10
    Extractionthe aqueous layer extracted with 3×75 ml of ether
11. 11
    Washwashed with saturated NaCl solution
12. 12
    Dryingdried (MgSO4)
13. 13
    Concentrationconcentrated in-vacuo
14. 14
    Otherto give further crude product
15. 15
    OtherThe crude product was recrystallized from hexanes

Procedure

To a stirred solution of 13.2 g (0.1403 mol) of phenol and 12.8 g (0.0998 mol) of 2,2,5,5-tetramethyltetrahydrofuran in 50 ml of heptane was added 13.1 g (0.0982 mol) of aluminum chloride in small portions. After the addition was complete the mixture was stirred at room temperature for 2.5 hours, at reflux for 2 hours and then at room temperature for a further 16 hours. The reaction mixture was then treated with 100 ml of 3N HCl and stirred for 0.5 hours. The mixture was filtered and the residue washed with water and dried in-vacuo to give crude product. The organic layer was separated from the filtrate and the aqueous layer extracted with 3×75 ml of ether. The organic layers were combined and washed with saturated NaCl solution, dried (MgSO4) and then concentrated in-vacuo to give further crude product. The crude product was recrystallized from hexanes to give the title compound as pale brown crystals. PMR (CDCl3): δ 1.26 (6 H, s), 1.28 (6H, s), 1.67 (4H, s), 5.08 (1H, broad s), 6.68 (1H, dd, J~8.7 Hz, 2.7 Hz), 6.82 (1H, d, J~2.7 Hz), 7.16 (1H, d, J~8.7 Hz).

Source