Reaktion #10473

Reaktionsgleichung

water

potassium tert-butoxide

cis-1,3-cyclohexanediol

benzyl bromide

→

desired compound

Ausbeute 50.6%

racemic cis-3-benzyloxycyclohexan-1-ol

Ausbeute 50.6%

Lösungsmittel

NMP

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGThe mixture was stirred at approx. 0° C. for 15 min
2. 2
   WaschenAfter washing three times with 700 ml of n-heptane
3. 3
   Extraktionthe aqueous solution was extracted four times with 500 ml of MTBE
4. 4
   WaschenThe combined MTBE phases were washed twice with in each case 1 l of water
5. 5
   Trocknendried (Na2SO4)
6. 6
   Einengensubsequently concentrated by evaporation under reduced pressure

Vorschrift

150.0 g (1.29 mol) of cis-1,3-cyclohexanediol were dissolved in 1.5 l of NMP, admixed with 111.6 g (0.99 mol) of potassium tert-butoxide (KOtBu) and stirred at 25–27° C. After about 30 minutes, the mixture was cooled to 0° C. and admixed dropwise with 78.1 g (0.46 mol) of benzyl bromide. The mixture was stirred at approx. 0° C. for 15 min and then 1.5 l of water were added. After washing three times with 700 ml of n-heptane and discarding the n-heptane solutions, the aqueous solution was extracted four times with 500 ml of MTBE. The combined MTBE phases were washed twice with in each case 1 l of water, dried (Na2SO4) and subsequently concentrated by evaporation under reduced pressure. 48.0 g of the desired compound were obtained as a clear, yellow oil; 1H NMR (CDCl3), δ =1.29 (m, 1H), 1.43–1.93 (m, 6H), 2.06 (m, 1H), 2.55 (s (br.), 1H), 3.56 (m, 1H), 3.74 (br, 1H), 4.55 (dd, 2H), 7.25–7.36 (m, 5H).

Quelle