Synthesis Of Nitrogenous Heterocyclics Based On Visible Light Photoredox Catalysis

Visible light is always recognized as an abundant and renewable energy source. Therefore the visible light photoredox catalysis, which takes advantage of the redox ability of special metal complex to engage in single-electron-transfer process with organic substrates upon excitation with visible light, has received much attention since its report in 2008. Through this technique various reactive species, including carbonyl radicals, trifluoromethyl radicals, arene radical cations, iminium ions and enone radical anions, were generated under very mild conditions. In this thesis we employed this approach in synthesis of phenanthridine derivatives and Luotonin A analogs.The first part of this thesis focused on applications of photoredox catalysis in somophilic isocyanide insertion. Here through photoredox catalysis, biaryl isocyanide insertion process was achieved, which showed an efficient access to 6-arylated and 6-trifluoromethylated phenanthridine derivatives. Optimizings were conducted and various substituted isocyanides were found to be compatible in these transformations with good to excellent chemical yields.The second part examined a photoredox catalysis strategy to introduce N-acylcyanamides as radical accepters in cyclization cascade processes. And this led to the synthesis of Luotonin A analogs. Initiaters including the toxic BU3SnH, AIBN and heat were avoided comparing to the traditional strategies. By changing the substrates, the rutaecarpine analog was also obtained through a similar process.