The first example of Pd-catalyzed, C3-selective arylation of unprotected pyridines has been developed by employing a catalytic system consisting of Pd(OAc)(2) and 1,10-phenanthroline. This protocol provides an expeditious route to an important class of 3-arylpyridines and 3-arylpiperidines frequently found in bioactive compounds. A brief synthesis of the drug molecule (±)-preclamol is also reported.

Pd-catalyzed C-3 selective olefination of pyridines is developed for the first time using 1,10-phenanthroline as the ligand. This finding provides a novel disconnection for the synthesis of pyridine-containing alkaloids and drug molecules as well as a new approach for developing Pd-catalyzed C-H functionalizations of pyridines.

A photocatalytic process for 1,7-enyne bicyclizations with α-bromo diethyl malonate has been established via synergistic domino bicyclizations. This protocol provides an efficient and practical method for the synthesis of various cyclopenta[c]quinolines and benzo[j]phenanthridines under operational simplicity and mild reaction conditions.

Palladium catalyzed, non-directed C3-selective arylation of pyridines with arenes and heteroarenes in the presence of 1,10-phenanthroline as the ligand has been developed. The optimized conditions allow for a highly C3-selective arylation of pyridines, affording various 3,3′-bipyridines and 3-arylpyridines.