A Convenient Palladium-Catalyzed Coupling Approach to 2,5-Disubstituted Pyridines

Article abstract of DOI:10.1021/jo00237a029

2,5-Dibromopyridine has been found to undergo a regioselective palladium-catalyzed coupling reaction with terminal acetylenes and arylzinc halides to give the corresponding 2-alkynyl-5-bromo- and 2-aryl-5-bromopyridines, respectively, in 70percent-90percent isolated yields.To complement this chemistry, the triflate derived from 2-methyl-5-pyridinol was found to participate in a palladium-catalyzed reaction with terminal acetylenes leading to the corresponding 5-alkynyl-2-methylpyridines.These intermediates can be further manipulated to afford a broad range of 2,5-disubstituted pyridines.