The reaction of 2,3-dichloromaleic anhydride with 2,3-diamino-1,4-naphthoquinone was studied and afforded to 1-(3-amino-1,4-dioxo-1,4- dihydronaphthalen-2-yl)-3,4-dichloro-1H-pyrrole-2,5-dione (3). Experimental techniques (NMR and single-crystal structures) confirmed the structure of 3. The study was extended to explore the failure of the intramolecular cyclization of 3 to the imidazole ring. Density Functional Theory at level B3LYP/6-31G(d,p) of theory were used to examine the optimized molecular geometry and to understand the reaction mechanism which reveals that the failure of cyclization is possibly due to positive charge of the amine in addition to the high repulsion between the naphthoquinone and the maleimide oxygens.

中文翻译：

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1-（3-Amino-1,4-dioxo-1,4-dihydronaphthalen-2-yl）-3,4-dichloro-1的结构和DFT研究

研究了2,3-二氯马来酸酐与2,3-二氨基-1,4-萘醌的反应，得到了1-（3-氨基-1,4-二氧代-1,4-二氢萘-2-基）- 3,4-二氯-1 H-吡咯-2,5-二酮（3 ）。实验技术（核磁共振和单晶结构）证实了3的结构。这项研究扩大到探索3的分子内环化的失败到咪唑环上 在理论的B3LYP / 6-31G（d，p）级上使用密度泛函理论研究了优化的分子几何结构并了解了反应机理，该机理揭示了环化失败可能是由于胺的正电荷以及萘醌和马来酰亚胺氧之间的高排斥力。