Reaktion #1746

Reaktionsgleichung

methylene chloride

O-acetyl-4-phenylcyclohexanol

paraformaldehyde

Hydrogen chloride

→

trans-O-Acetyl-4-(4-chloromethylphenyl)-cyclohexanol

Lösungsmittel

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigerises to about 30° C.
2. 2
   Sonstigea substantially homogeneous solution is formed
3. 3
   Sonstigeto react for 15 hours at ambient temperature
4. 4
   SonstigeThe organic phase is separated off
5. 5
   Extraktionthe aqueous phase is extracted with methylene chloride again
6. 6
   WaschenThey are washed until neutral,
7. 7
   Sonstigedried
8. 8
   Sonstigeevaporated in vacuo
9. 9
   SonstigeThe yellow oil remaining is crystallised by trituration with diisopropylether
10. 10
    Sonstigethe solid product is recrystallised from diisopropylether
11. 11
    SonstigeWhite crystals are obtained

Vorschrift

A solution of 24.3 g (0.11 mol) of O-acetyl-4-phenylcyclohexanol in 1300 ml of methylene chloride is combined with 26.0 g (0.86 mol) of paraformaldehyde and 26.0 g (0.19 mol) of zinc chloride. Hydrogen chloride is introduced into this suspension, with stirring, for 2.5 hours, whilst the temperature rises to about 30° C. and a substantially homogeneous solution is formed. The mixture is then allowed to react for 15 hours at ambient temperature and the reaction mixture is then hydrolysed with stirring in about 1.5 litres of ice water. The organic phase is separated off, the aqueous phase is extracted with methylene chloride again and the two organic phases are combined. They are washed until neutral, dried and evaporated in vacuo. The yellow oil remaining is crystallised by trituration with diisopropylether and the solid product is recrystallised from diisopropylether. White crystals are obtained, melting point 87°-89° C.

Quelle