Oxidation potentials correlate with conductivities of aromatic molecular wires.

4,4'-(1,4-naphthalenediyl)bisbenzamine (8). To a solution of 188 mg (0.657 mmol) of 1,4dibromonaphthalene in 10 mL of toluene was added 120 mg (0.104 mmol) of tetrakis(triphenylphosphine) palladium and the mixture was stirred at room temperature for 30 min. To the solution was added 1.3 mL (2M, 2.6 mmol) of aqueous sodium carbonate followed by 288 mg (1.31 mmol) of 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-aniline (Aldrich) in 10 mL of ethanol. The resulting mixture was heated at reflux for 5.5 h. The mixture was cooled to room temperature and partitioned between 25 mL of water and 25 mL of ethyl acetate. The organic layer was removed and the aqueous layer was extracted with 25 mL of ethyl acetate. The combined organic layers were dried over sodium sulfate, filtered, concentrated in vacuo and purified by flash chromatography on silica gel using 3:1 hexane:ethyl acetate to 1:1 hexane:ethyl acetate. The oily product fraction was dissolved in 2 mL of ethyl acetate and was treated with ca. 10 mL of hexanes until the solution became slightly cloudy. The product precipitated as a pale yellow solid (91 mg, 45% yield). A portion was sublimed at 200-220 oC under vacuum for conductance and electrochemical measurements. H NMR (CDCl3, 400 MHz) δ 8.03-8.01 (m, 2H), 7.42-7.32 (m, 8H), 6.84-6.82 (m, 4H), 3.77 (br s, 4H); APCI-MS (MeOH/Me2CO): 311 (M+H).