Vedazyl radicals as substrates for the synthesis of small molecule and polymer heterocycles.

点击翻译按钮获取中文摘要

As the need for new compounds for drug therapy and new materials for increasingly sophisticated applications, as for example in the field of electronics, continues, the pressures on the synthetic chemist to develop these materials continue to increase. One way of developing new materials and compounds is to develop new pathway for their synthesis. In this submission we propose the use of verdazyl radicals, a very interesting class of radicals that can be isolated and stored, as substrates for organic synthesis. Despite having being discovered over 35 years ago, verdazyl radicals have never been used as substrates for organic synthesis in spite of their wealth of structural variance, and the fact that they contain numerous hetero atoms, especially nitrogen and oxygen atoms. These structural features suggest that they could be excellent substrates for a variety of interesting and unique first generation heterocyclic compounds, both polymeric, supramolecular (in this case as exemplified by cyclophanes, or more precisely, hetereaphanes) and small molecules, which can be made to undergo unique rearrangements to provide a second generation of compounds. Most new synthetic drugs are heterocyclic compounds and the molecular scaffolds we are proposing have been found in many of these drugs. In addition we are proposing to use this chemistry to make unique heterocyclic block copolymers that could be used in self-assembly studies, presently one of the most active areas of polymer research. The recent discovery in our laboratory that verdazyl radicals will react with themselves to produce azomethine imines that can undergo concerted cycloaddition reactions with electron-poor dipolarophiles have already led to the synthesis of heterocyclic containing pyrazole, triazole and oxadiazolone backbones, backbones commonly found in many drugs.