[O:1]=[C:2]([C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1)[CH2:3][C:4]#[N:5].[CH2:12](O)[CH2:13][OH:14]>C1(C)C=CC=CC=1.CC1C=CC(S(O)(=O)=O)=CC=1>[C:6]1([C:2]2([CH2:3][C:4]#[N:5])[O:14][CH2:13][CH2:12][O:1]2)[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1To a solution of 3-oxo-3-phenylpropanenitrile (10 g, 69 mmol) and PTSA (27 mg, 1.37 mmol) in toluene (120 mL) is added ethylene glycol (120 mL, 2057 mmol). The azeotropic mixture is heated at 150° C. for 14 h. The solvent is evaporated under reduced pressure and the residue is washed with 10% aqueous NaOH solution. The aqueous layer is extracted with diethyl ether (2×100 mL) and the combined organic layers are dried (Na2SO4) and evaporated to provide the crude compound. The crude material is purified over neutral alumina eluting with 1% of ethyl acetate/hexane to afford the title compound as an off-white solid (10 g, 77%).
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