Abstract A heterocyclic compound commonly known as “indanocyclon” undergoes an unexpected Diels-Alder addition with maleimide. The resulting product has been isolated and characterized in order to get an information about its structure and possible mechanism of the reaction. Extensive comparison of single crystal properties of 3-(2,8-dioxo-1,3-diphenyl-2,8-dihydrocyclopenta[a]inden-8a(1H)-yl)pyrrolidine-2,5-dione and favorable product of the reaction has been also performed.

中文翻译：

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“茚满环”与马来酰亚胺发生狄尔斯-阿尔德反应的意外产物

摘要 一种通常被称为“茚满环”的杂环化合物与马来酰亚胺发生意想不到的狄尔斯-阿尔德加成反应。所得产物已被分离和表征，以便获得有关其结构和可能的反应机理的信息。3-(2,8-dioxo-1,3-diphenyl-2,8-dihydrocyclopenta[a]inden-8a(1H)-yl)pyrrolidine-2,5-dione 的单晶性质的广泛比较也进行了反应。