Reaktion #445453

Reaktionsgleichung

methyl iodide

6,7-Dichloro-2-cyclopentyl-2,3-dihydro-5-methoxy-1H-inden-1-one

Sodium hydride

5,6-dichloro-2-cyclopentyl-2,3-dihydro-5-methoxy-2-methyl-1H-inden-1-one

hydrogen

→

6,7-Dichloro-2-cyclopentyl-2,3-dihydro-5-methoxy-2-methyl-1H-inden-1-one

Lösungsmittel

1,2-dimethoxyethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe solution is cooled
2. 2
   Temperaturto reflux
3. 3
   Temperaturcooled
4. 4
   SonstigeMost of the 1,2-dimethoxyethane is evaporated
5. 5
   workup.ADDITIONwater is added to the residue which
6. 6
   Sonstigeis crystallized from methylcyclohexane and from ethanol-water (4:1)
7. 7
   Sonstigeto obtain 3.4 g

Vorschrift

6,7-Dichloro-2-cyclopentyl-2,3-dihydro-5-methoxy-1H-inden-1-one (7.5 g., 0.025 mole) is dissolved in dry 1,2-dimethoxyethane (200 ml.) under nitrogen. Sodium hydride (57% in mineral oil; 1.16 g., 0.0275 mole) is then added and the mixture is stirred at 80° until evolution of hydrogen ceases (2 hours). The solution is cooled and methyl iodide (7.5 ml.) is added, the mixture is again brought to reflux and then cooled. Most of the 1,2-dimethoxyethane is evaporated and water is added to the residue which soon solidifies and is crystallized from methylcyclohexane and from ethanol-water (4:1) to obtain 3.4 g. of 5,6-dichloro-2-cyclopentyl-2,3-dihydro-5-methoxy-2-methyl-1H-inden-1-one, m.p. 109°-111.5° C.

Quelle