Synthesis and Studies of Pyridoneimine-Functionalized PETIM Dendrimers.

Pyridinoimine-functionalized poly(ether imine) (PETIM) dendrimers of 1-3 generations, possessing 4-16 moieties at the peripheries, are synthesized. Chloride-functionalized dendrimers are reacted with -methylamino pyridine, under basic conditions, which led to functionalization of the peripheries of a dendrimer with pyridoneimine moieties. Variable-temperature H NMR studies are performed to assess the contributing resonance forms of pyridoneimine in the dendrimers. Solvatochromism and N NMR studies aid further the assessment of the contributing resonance forms. Comparison with derivatives that possess 1 and 2 pyridoneimines illustrates the contributing resonance forms between nonaromatic pyridoneimine and zwitter ionic aromatic imidopyridinium species.