A 250-mL, three-necked, round-bottomed flask equipped with a dry ice-acetone cooled reflux condenser, addition funnel, and a gas inlet was charged with liquid ammonia (175 mL). Iron (III) nitrate nonahydrate (0.23 g, 0.57 mmol) was added to the liquid NH3 in one portion as a solid, and then potassium metal (4.2 g, 107.4 mmol) was added cautiously in small portions. A solution of 2,4-dimethylbenzonitrile (7.0 g, 53.4 mmol) in THF (20 mL) was added to the reaction mixture dropwise over a period of 5 minutes, the reaction was stirred for 15 minutes, a solution of 1-cyanonaphthalene (12.6 g, 79.8 mmol) in THF (30 mL) was then added dropwise over a period of 10 minutes, and the reaction mixture was allowed to stir overnight as the liquid ammonia gradually evaporated. The crude reaction mixture was cautiously poured into excess ice water. The layers were separated, and the aqueous phase was extracted with methylene chloride. The combined organic extracts were dried and concentrated. The residue was purified by flash chromatography with 2:1 hexane-ethyl acetate, and the crude product was recrystallized from 2:1 hexane-ethyl acetate to afford the title compound (3.82 g, 13.4 mmol, 24% yield) as a solid: mp 170°; IR(CHCl3) 3512, 3409 cm-1 ; MS m/e 285(M+ +H); 1H NMR(CDCl3) δ 8.13-8.23(m,1H), 7.80-7.97(m,2H), 7.62-7.78(m,2H), 7.37-7.61(m,1H), 7.27-7.36(m,1H), 7.17-7.26(m,1H), 5.28(s,2H), 2.51(s,3H); HRMS m/e calcd for C20H16N2 (M+) 284.1315, Found 284.1305. Anal. Calcd for C20H16N2 : C,84.48; H,5.67; N,9.85. Found: C,84.39; H,5.63; N,9.57.
