1-Methyl-2-(thiophen-3-yl)-1H-benzimidazole was synthesized by the Weidenhagen reaction, followed by N-methylation. Electrophilic substitution reactions of the title compound, in particular nitration, bromination, sulfonation, formylation, and acylation, were studied. The formylation and acylation in polyphosphoric acid afforded mixtures of 2- and 5-substituted isomers at the thiophene ring. The nitration of 1-methyl-2-(thiophen-3-yl)-1H-benzimidazole involved the thiophene ring or both thiophene and benzene fragments, depending on the conditions. Steric arrangement of the heterocycles in the 1-methyl-2-(thiophen-3-yl)-1H-benzimidazole molecule was analyzed by quantum chemical calculations.

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1-甲基-2-（噻吩-3-基）-1 H-苯并咪唑的合成及一些转化

通过Weidenhagen反应，然后N-甲基化，合成1-甲基-2-（噻吩-3-基）-1 H-苯并咪唑。研究了标题化合物的亲电取代反应，特别是硝化，溴化，磺化，甲酰化和酰化。多磷酸中的甲酰化和酰化作用在噻吩环上提供了2和5个取代异构体的混合物。1-甲基-2-（噻吩-3-基）-1 H-苯并咪唑的硝化涉及噻吩环或噻吩和苯片段，具体取决于条件。通过量子化学计算分析了1-甲基-2-（噻吩-3-基）-1 H-苯并咪唑分子中杂环的立体排列。