Synthesis of Functionalized Phenanthrenes via Regioselective Oxidative Radical Cyclization
作者:Kamalkishore Pati、Christopher Michas、David Allenger、Ilya Piskun、Peter S. Coutros、Gabriel dos Passos Gomes、Igor V. Alabugin
DOI:10.1021/acs.joc.5b01014
日期:2015.12.4
preparation of fully conjugated molecules. In this work, we report an oxidatively terminated Bu3Sn-mediated cyclization of an alkyne where AIBN, the commonly used initiator, takes on a new function as an oxidative agent. Sn-mediated radical transformation of biphenyl aryl acetylenes into functionalized phenanthrenyl stannanes can be initiated via two potentially equilibrating vinyl radicals, one of which can
大多数Sn介导的环化反应都是还原性的,因此无法得到完全结合的产物。这是在Sn介导的自由基级联用于制备完全共轭分子的应用中的限制。在这项工作中,我们报告了氧化终止的Bu 3Sn介导的炔烃环化反应,其中常用的引发剂AIBN作为氧化剂起新的作用。可以通过两个可能平衡的乙烯基自由基引发联苯芳基乙炔的Sn介导的自由基转化为官能化的菲蒽锡,其中一个可以被联苯部分的快速6内环合捕获,收率好至极好。Sn取代菲的有效制备为大型聚芳烃的构建提供了方便的构建基块。