[H-].[Na+].[CH:3]1([C:9]([O:11]CC)=O)[CH2:8][CH2:7][CH:6]=[CH:5][CH2:4]1.[C:14](#[N:16])[CH3:15]>C1(C)C=CC=CC=1>[CH:3]1([C:9]([CH2:15][C:14]#[N:16])=[O:11])[CH2:8][CH2:7][CH:6]=[CH:5][CH2:4]1To a suspension of 1.25 g (2.60 mM) of 50% sodium hydride in 10 ml of toluene is added dropwise a solution of 2.01 g (1.30 mM) of ethyl 3-cyclohexenylcarboxylate 11 and 0.96 g (2.34 mM) of acetonitrile in 4 ml of toluene under nitrogen atmosphere in an hour and the mixture is stirred at 85° C. for 8 hours. After cooling, ice-cold water is added to the mixture. The aqueous phase is separated, washed with toluene, made acid with 10% hydrochloric acid and extracted with toluene. The extracted solution is washed with a dilute aqueous sodium hydrogencarbonate, and then with water, dried on magnesium sulfate and evaporated under reduced pressure. The resulting residue is chromatographed over silica gel and eluted with chloroform to give 1.91 g of the titled compound 8 as an yellow oil in 98.4% yield,
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