Toluene → Ethyl 2-(1-methyl-2-oxocyclopentyl)acetate

Reaktionsgleichung

C1(C)C=CC=CC=1.[CH3:8][CH:9]1[CH2:13][CH2:12][CH2:11][C:10]1=[O:14].Br[CH2:16][C:17]([O:19][CH2:20][CH3:21])=[O:18]>C1C=CC=CC=1>[CH2:20]([O:19][C:17](=[O:18])[CH2:16][C:9]1([CH3:8])[CH2:13][CH2:12][CH2:11][C:10]1=[O:14])[CH3:21]

Komponenten

Versuchsvorschrift

A solution of sodium tert.-amylate in toluene (70 ml, 0.1 mole) is added dropwise with stirring under an atmosphere of nitrogen to a solution of 2-methylcyclopentanone (9.8 g, 0.1 mole) and ethyl bromoacetate (16.7 g, 0.1 mole) in dry benzene (100 ml). The reaction is exothermic, a precipitate is formed, and the mixture turns yellow-orange. Stirring is continued for 3 hrs. at room temperature, the solution is washed with 1% HCl, cold water, and brine, dried over anhydrous magnesium sulfate and the solvent evaporated to yield 1-methyl-2-oxocyclopentane acetic acid ethyl ester as a pale yellow oil which is used without further purification in the subsequent step and which is identical with the same compound described in Example 5.