C(O)C.[Na].[CH3:5][O:6][C:7]1[CH:8]=[C:9]([CH2:15][C:16]#[N:17])[CH:10]=[CH:11][C:12]=1[O:13][CH3:14].[C:18](=O)([O:22]CC)[O:19][CH2:20][CH3:21]>C1(C)C=CC=CC=1.C(OCC)(=O)C.CCCCCC>[CH2:20]([O:19][C:18](=[O:22])[CH:15]([C:16]#[N:17])[C:9]1[CH:10]=[CH:11][C:12]([O:13][CH3:14])=[C:7]([O:6][CH3:5])[CH:8]=1)[CH3:21]
Ethanol (13 mL, 225) was added to a suspension of sodium (3.6 g, 157 mmol) in toluene (125 mL) with stirring at 85° C. The reaction mixture turned to a slightly turbid white mixture. 3,4-Dimethoxy phenylacetonitrile (26.6 g, 150 mmol) was added to the reaction mixture at one time and the mixture was stirred at 85° C. for 30 minutes. Diethyl carbonate (20 mL, 16.5 mmol) was added to the mixture. The mixture was heated at 110° C. for 5 hrs. The solvent was evaporated and ice (250 g) was added. The mixture was neutralized to pH=7 by addition of acetic acid (20 mL). The aqueous phase was extracted with ethyl acetate (3×20 mL). The combined extracts were washed with saturated aqueous sodium chloride solution (50 mL), dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 70–230 mesh, 40% ethyl acetate/hexane) afforded cyano-(3,4-dimethoxy-phenyl)-acetic acid ethyl ester (18.1 g, 49% yield) as a colorless oil.
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