The Ullmann cross-coupling reaction of halopyridines with 2-bromonitrobenzenes was successfully catalyzed by low valent palladium [Pd(PPh3)4, PdCl2(PPh3)2, PdCl2] to afford (2-nitrophenyl)pyridine derivatives in good to excellent yield.
SHIBUYA, KIMIYUKI;TAKAHASHI, YOSHIO;SHIGYO, HIROMICHI;OHTA, TOMIO, HETEROCYCLES, 29,(1989) N1, C. 2199-2207