General procedure for the synthesis of 6,6'-dicyano-2,2'-bipyridine from 2-bromo-6-cyanopyridine: To a solution of DME (42.4 mg, 1.0 mmol, 2.0 eq.) containing NiCl2-complex (0.01 mmol, 0.02 eq.), Zr(cp)2Cl2 (7.3 mg, 0.025 mmol, 0.05 eq.), Mn powder (54.9 mg, 1.0 mmol 2.0 eq.) and LiCl (42.4 mg, 1.0 mmol, 2.0 eq.) were added to a solution of 2-bromo-6-cyanopyridine (0.5 mmol) in DME (1.0 mL). The reaction mixture was stirred at room temperature until the reaction was complete (monitored by TLC). For bipyridine synthesis, after completion of the reaction, the reaction was quenched with water and NH4OH (27% w/w, 0.6 mL), stirred for 10 min, and then extracted with CH2Cl2 (10 mL x 3). The organic phase was washed with brine (15 mL), dried over Na2SO4, filtered and concentrated under reduced pressure. The residue was purified by rapid chromatography on silica gel to afford the target product 6,6'-dicyano-2,2'-bipyridine. For the reaction of the alkenyl halide substrate, the reaction was carried out on a 0.2 mmol scale (0.5 M concentration) with the addition of toluene (42 μL, 0.4 mmol, 2.0 eq.) as an internal standard. Upon completion of the reaction, a small portion of the reaction mixture (50 μL) was taken through a silica gel pad, eluted with CDCl3 (1 mL), and the yield was estimated by 1H NMR (600 MHz, CDCl3).
