We reported here a facile synthesis of dibenzo[a,e]cyclo­octene-5,11(6H,12H)-diones via dimerization of benzocyclobutenones in the presence of simple base via the elusive benzocyclobutenone anion­. The temperature effect played a crucial role in the dimerization reaction­. Further synthesis of 5,11-disubstituted dibenzo[a,e]cyclo­octenes (dibenzo[a,e][8]annulenes) from dibenzo[a,e]cyclooctene-5,11(6H,12H)-diones was also explored.

中文翻译：

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通过难以捉摸的苯并环丁烯酮阴离子合成二苯并[a,e]环辛烯-5,11(6H,12H)-二酮

我们在这里报道了在简单碱的存在下，通过难以捉摸的苯并环丁烯酮阴离子，通过苯并环丁烯酮的二聚化，轻松合成二苯并 [a,e] 环辛烯-5,11(6H,12H)-二酮。温度效应在二聚反应中起关键作用。还探索了从二苯并[a,e]环辛烯-5,11(6H,12H)-二酮进一步合成5,11-二取代的二苯并[a,e]环辛烯(dibenzo[a,e][8]annulenes)。