2.4.6- Triphenylpyridine reacts with

Grignard and organolithium reagents react with tetrachloro-4-methoxypyridine to form 4-alkyl-and 4-aryltetradilorcpyridines.Phenyllithium and tetrachloro-4-methoxypyridine form tetrachloro-4-phenyl- (MI-737, Ar = CgHs) trichloro-4,6-diphenyl- and dichloro-2,4,6-triphenylpyridine. Under mild conditions a series of aryllithium compounds form 4-aryltetra-chloropyridines (XII-737) that react with butyllithium to give 4-aryl-trichloro-3-pyridyllithium (Xn-738). - ... 

The most unexpected by-product of the reaction in this case is 2,3,6-triphenylpyridine. Probably, benzyl phenyl ketone (the usual product of partial deoximation of oximes in the conditions for synthesis of pyrroles) condenses with acetaldehyde (product of acetylene hydration in superbase media [105], Equation 1, Scheme 1.166) to form an equilibrium mixture of ethylenic ketones I and J (Equation 2). The ketone J reacts with benzylamine to close 2,3,6-triphenyltetrahydropyridine cycle K. The latter aromatizes to the pyridine (Equation 3). 

Chen et al. [137] employed microwave irradiation for the preparation of amine-or anhydride-terminated hb-PIs. A BB 2-type triamine monomer, namely 2,4,6-tris (4-aminophenyl)pyridine (TAPP) (1-16, Scheme 9a), was synthesized under microwave irradiation to prepare a series of amine- and anhydride-terminated triphenylpyridine-containing hb-PIs by A2 + BB 2 polymerization. Several commercially available aromatic dianhydrides, namely pyromellitic dianhydride (PMDA, 1-23, Scheme 9b), BTDA, and ODPA, were used as A2 type monomers to react with the BB 2 type aromatic triamine (TAPP). The addition of dianhydride to triamine with a monomer molar ratio of 1 1 yielded the amine-terminated polymer, whereas the reverse monomer addition order with a molar ratio of 2 1 gave the anhydride-terminated polymer. Slow monomer addition was used to avoid any high local concentration. The authors kept the total solid content below 0.08 mol/L for the amine-terminated polymer and 0.06 mol/L for the anhydride-terminated polymer to prevent insoluble gels. During the whole polymerization, continuous microwave irradiation was employed to enhance the reactivity and... 

---