2-nitrobenzyl chloride (Aldrich)
Potassium hydroxide
Ethanol (Fischer Scientific)

To 2-nitrobenzyl chloride (5.05 g, 29.43 mmol) in EtOH (20 ml) was added slowly KOH (8.26 g, 148 mmol) in warm EtOH (50 ml) with vigorous stirring. The mixture became warm. The mixture was stirred overnight, and a yellow precipitate was recovered by filtration, washed with EtOH, and recrystallized from ethyl acetate, yielding 2,2’-dinitrostilbene as needle like yellow crystals (1.39 g, 17.5%).

¹H NMR 400 MHz (CDCl₃): δ ppm 8.04 (dd, ⁴J_HH = 1 Hz, ³J_HH = 8 Hz, 2H, ArH), 7.81 (dd, ⁴J_HH = 1 Hz, ³J_HH = 8 Hz, 2H, ArH), 7.67 (td, ⁴J_HH = 1 Hz, ³J_HH = 8 Hz, 2H, ArH), 6.57 (s, 2H, CH=CH), 7.48 (td, ⁴J_HH = 1 Hz, ³J_HH = 8 Hz, 2H, ArH)

¹³C{¹H} NMR 100 MHz (CDCl₃): δ ppm 147.9, 133.7, 132.6, 129.1, 128.9 124.9 (Ar) 130.0 (C=C)

EA: found (calc) C: 62.12 (62.22), H: 3.69 (3.73), N: 10.21 (10.37)

MS (EI⁺): m/z 270 (M⁺)

A. Blanc and C. G. Bochet, J. Org. Chem., 2003, 68, 1138-1141. http://dx.doi.org/10.1021/jo026347x