作者:Philipp Röse、Carmen Carlota Magraner Garcia、Florian Pünner、Klaus Harms、Gerhard Hilt
DOI:10.1021/acs.joc.5b01198
日期:2015.7.17
The [4 + 2] cross-benzannulation of conjugated enynes and diynes under cobalt-catalysis led to 1,2,3-trisubstituted benzene derivatives in good yields. The reaction proceeds smoothly in absolute regiospecific control when symmetrical diynes are applied. Moreover, the use of unsymmetrical diynes was investigated, resulting in the formation of the unprecedented regioisomers as major products, which is
共轭烯和二炔在钴催化下的[4 + 2]交叉苯甲酸酯化反应可得到1,2,3-三取代苯衍生物,收率很高。当应用对称二炔时,反应在绝对区域特异性控制下顺利进行。此外,研究了不对称二炔的使用,导致形成了前所未有的区域异构体作为主要产物,这与钯催化的苯环化反应获得的结果相反。同样,可以将4-溴苯基取代的起始原料成功地应用于钴催化的过程中,这在钯催化的对应物中可能是有问题的。