An efficient Pd-catalyzed double annulation reaction of 1-(2,6-dibromophenyl)-1H-pyrroles with arynes is developed to synthesize π-extended dibenzo[d,k]ullazines in good to excellent yields. For the first time, the parent dibenzo[d,k]ullazine core is obtained and characterized.

中文翻译：

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钯催化双环烷烃芳烃合成π-扩展的二苯并[ d，k ] ullazines

开发了一种高效的Pd催化1-（2,6-二溴苯基）-1 H-吡咯与芳烃的双环合反应，以良好的收率合成了π扩展的二苯并[ d，k ] ullazines。首次获得并表征了母体二苯并[ d，k ] ullazine核。