Reaktion #820035

Reaktionsgleichung

HCl

3-hydroxy-1-(2,6,6-trimethyl-3-cyclohexen-1-yl)-1-butanone

pyridine

ethyl chloroformate

→

ethyl trans-1-methyl-3-oxo-3-(2,6,6-trimethyl-3-cyclohexen-1-yl)propyl carbonate

Reaktionsbedingungen

Aufarbeitung

1. 1
   Extraktionextracted twice with ether
2. 2
   Waschenwashed with water, saturated aqueous NaHCO3
3. 3
   Trocknenwith saturated aqueous NaCl, dried over Na2SO4
4. 4
   Einengenconcentrated
5. 5
   SonstigeThe oil thus obtained
6. 6
   Sonstigewas purified by flash-chromatography (cyclohexane/AcOEt=98:2)

Vorschrift

A solution of 3-hydroxy-1-(2,6,6-trimethyl-3-cyclohexen-1-yl)-1-butanone (2.00 g, 84% pure, 8.0 mmol) in pyridine (1.85 g, 23.4 mmol) was treated at 0° C. with ethyl chloroformate (1.24 g, 23.4 mmol). The reaction solution was stirred at room temperature for 36 hours, treated with aqueous 5% HCl and extracted twice with ether, washed with water, saturated aqueous NaHCO3, then with saturated aqueous NaCl, dried over Na2SO4 and concentrated. The oil thus obtained was purified by flash-chromatography (cyclohexane/AcOEt=98:2), using SiO2 (100 g). Yield: 2.06 g (78%).

Quelle