A new and straightforward method for the synthesis of 5-bromotetracenes through PBr₃-mediated cyclization of 1,7-diyn-3,6-bis(propargyl carbonate)s has been developed. This method offers several advantages such as easily accessible starting materials, high efficiency, and wide functional group compatibility. In addition, chloro- and iodo-substituted tetracenes were also synthesized using appropriate halogenating reagents. The utility of the 5-bromotetracene products has been illustrated by their efficient transformations through various palladium-catalyzed cross-coupling reactions.

中文翻译：

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PBr ₃介导的1,7-Diyn-3,6-双（炔丙基碳酸酯）s的环化：5-溴代曲烯的合成

已开发出一种新的直接方法，可通过PBr ₃介导的1,7-二炔-3,6-双（碳酸炔丙基酯）的环化反应合成5-溴代四氢呋喃酮。该方法具有许多优点，例如容易获得的起始原料，高效率和广泛的官能团相容性。另外，还使用适当的卤化试剂合成了氯和碘取代的四碳烯。5-溴并四苯产物的实用性已通过各种钯催化的交叉偶联反应的有效转化得到了说明。