The Use of Cobalt-Mediated Cycloisomerisation of Ynedinitriles in the Synthesis of Pyridazinohelicenes
作者:Serghei Chercheja、Jiří Klívar、Andrej Jančařík、Jiří Rybáček、Simon Salzl、Ján Tarábek、Lubomír Pospíšil、Jana Vacek Chocholoušová、Jaroslav Vacek、Radek Pohl、Ivana Císařová、Ivo Starý、Irena G. Stará
DOI:10.1002/chem.201402312
日期:2014.7.1
A cobalt‐mediated [2+2+2] cycloisomerisation of ynedinitriles to helical pyridazines in good to high yields was developed. The construction of the pyridazine nucleus from one alkyne and two nitrile units is proposed to follow either a conventional organometallic mechanism or to be triggered by a single‐electron transfer from a CoII species. Various [5]‐, [6]‐ and [7]helicene pyridazines were prepared