SYNTHETIC ROUTES TO NITROAMINO PRECURSORS OF THE FOOD CARCINOGEN -AMINO-1-METHYL-6-PHENYL-1H-IMIDAZO4,5-B!PYRIDINE AND ITS 3-METHYL ISOMERVIA PD(0)-CATALYZED ARYLATION

The synthesis of the novel key intermediates 3-methylamino-2-nitro- an d 2-methyl-amino-3-nitro-5-phenylpyridine, and some of their derivativ es substituted in the benzene ring, from 5-bromonicotinic acid, 3-brom o-5-methoxypyridine, 2-chloro-3-nitropyridine, 2-amino-5-bromopyridine or 5-bromo-2-methoxypyridine is described. Palladium(0)-mediated aryl ation of bromopyridines with areneboronic acids was an essential step in the syntheses.