A New Class of Pyrazolopyridine Nucleus with Fluorescent Properties, Obtained through Either a Radical or a Pd Arylation Pathway from N-Azinylpyridinium N-Aminides
摘要:
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.
N-Azinylpyridinium N-Aminides: An Approach to Pyrazolopyridines via an Intramolecular Radical Pathway
作者:Araceli Nuñez、Aránzazu García de Viedma、Valentín Martínez-Barrasa、Carolina Burgos、Julio Alvarez-Builla
DOI:10.1055/s-2002-32596
日期:——
has been devoted to pyridyl radicals; both Snieckus 3 and Nadin 4 have reported pyridyl radicalcyclisations. Harrowven 5 has published some papers, which include pyridyl radicalcyclisations and aryl radicalcyclisations onto pyridines. Jones 6 has disclosed the use of radicalsderived from 3-bromopyridine and the exten- sion of this chemistry to pyridinium radicals. 7 However, to the best of our
A New Class of Pyrazolopyridine Nucleus with Fluorescent Properties, Obtained through Either a Radical or a Pd Arylation Pathway from <i>N</i>-Azinylpyridinium <i>N</i>-Aminides
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.