A new class of pyrazolopyridine nucleus with fluorescent properties, obtained through either a radical or a Pd arylation pathway from N-azinylpyridinium N-aminides

Article abstract of DOI:10.1021/jo801549u

(Chemical Equation Presented) The synthesis of dipyridopyrazole and pyridopyrazolopyrazine derivatives - both of which incorporate a 3-aryl moiety - can be achieved in moderate yields by intramolecular radical arylation of pyridinium N-aminides using tris(trimethylsilyl)silane and azobisisobutyronitrile. Improved results were obtained on using Pd direct arylation in conjunction with microwave irradiation. A preliminary study into the fluorescent properties of the target compounds is also reported.