Reaktion #160677

Reaktionsgleichung

hydrochloric acid

3,4-dimethoxy-ω-nitrostyrene

2-trimethylsilyloxy-1,3-butadiene

Toluene

→

title compound

(3RS,4SR)-3-(3,4-Dimethoxyphenyl)-4-nitrocyclohexanone

Lösungsmittel

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturcooled
2. 2
   workup.ADDITIONare dropped
3. 3
   workup.STIRRINGunder stirring
4. 4
   SonstigeThe phases are separated
5. 5
   Extraktionthe aqueous layer is extracted three times with dichloromethane
6. 6
   WaschenThe combined organic extracts are washed with saturated sodium hydrogencarbonate solution
7. 7
   Trocknendried over magnesium sulfate
8. 8
   Sonstigethe solvents are removed under reduced pressure
9. 9
   Sonstigeto give 150 g of the crude title compound
10. 10
    SonstigeFurther purification

Vorschrift

90.0 g of 3,4-dimethoxy-ω-nitrostyrene (compound G2), 90 ml of 2-trimethylsilyloxy-1,3-butadiene and 180 ml of abs. Toluene are put in an autoclave, where the mixture is stirred at 140° C. for 2 days and then cooled. After addition of 1000 ml of ethyl acetate, 300 ml of a 2 N solution of hydrochloric acid are dropped under stirring. The phases are separated and the aqueous layer is extracted three times with dichloromethane. The combined organic extracts are washed with saturated sodium hydrogencarbonate solution, dried over magnesium sulfate and the solvents are removed under reduced pressure to give 150 g of the crude title compound. Further purification is carried out by chromatography on silica gel using petroleum ether/ethyl acetate in the ratio 1/1 as eluent to give 81.5 g (67% of theory) of the pure title compound.

Quelle