Dimethylformamide → 4′-(4-Methoxyphenyl)[2,2′:6′,2′′-terpyridine]-6,6′′-dicarbonitrile

Participants

Reaction Steps

To a solution of 6,6'-dibromo-4'-(4-methoxyphenyl)-2,2':6',2"-terpyridine from example 6 (30.0 g, 0.06 mole) in anhydrous dimethyl formamide (Aldrich HPLC grade, 240 mL) in a 500 mL 3 neck round bottom flask equipped with a condenser, nitrogen inlet adapter, and a mechanical stirrer (glass rod with teflon blade) was added cuprous cyanide (Aldrich, 21.5 g, 0.24 mole) and sodium cyanide (Aldrich, 11.8 g, 0.24 mole) under efficient stirring and nitrogen flow. The mixture was heated on an oil-bath equipped with a temperature controller for about five hours at 155° to 160° C. The reaction mixture was then filtered at 150° C. to remove hazziness. The filtrate was evaporated to dryness under vacuum at 65° to 70° C. The residue was treated with water (30 mL) and stirred with sodium cyanide solution (20.00 g sodium cyanide into 80 mL of water) for about 3 to 4 hours at about 45° C. The crystalline mass of 6,6"-dicyano-4'-(4-methoxyphenyl)-2,2':6',2"-terpyridine was isolated by filtration, washed with water (250 mL), and then dried under vacuum for 16 hours at 50°-55° C. to yield 22.2 g of tan colored product (95 % of theory). The crude product was recrystallized from methylene chloride (1 g in 90 mL). TLC: (silica gel plate; ethyl acetate:hexane::1:1 v/v) showed a single spot (Rf=0.5 approx.). Infrared spectrum: nitrile band around 2200 cm-1 ; mass spectrum (FAB): M+H=390 m/e; 1H NMR (CDCl3): 3.9 (s, 3H, OCH3), 7.1 (d, 2H), 7.77 (d, 2H), 7.87 (d, 2H), 8.03 (t, 2H), 8.79 (s, 2H) and 8.85 ppm (d, 2H).

Provenance & Evidence