Abstract Whereas 2, 3-dichloropyridine and 2, 5-dichloro-4-(lithiooxy) pyridine undergo deprotonation exclusively at the 4-and 2-positions, respectively, optional site selectivity can be implemented with 2, 5-and 3, 4-dichloropyridine (which are attacked, depending on the choice of the reagents, at either the 4-or 6-and either the 2-and 5-positions, respectively). Upon treatment with lithium diisopropylamide, 2, 4-dichloro-3-iodopyridine, 3, 5-dichloro-4 ...
