N-Heterocyclic carbene derived 2-phenylthiocarbamoyl benzimidazolium and imidazolinium inner salts are a unique ambident CâCâS and CâCâN 1,3-dipolar system able to undergo highly efficient and regioselective cycloaddition with dimethyl acetylenedicarboxylate and ethyl propiolate to furnish, respectively, spiro[imidazole-2,3â²-thiophene] and spiro[imidazole-2,3â²-pyrrole] derivatives in good to excellent yields.
由 N-杂环碳烯衍生的 2-苯基
硫代
氨基甲酰
苯并咪唑鎓和
咪唑啉鎓内盐是一种独特的 CâCâS 和 CâCâN 1、3 双极体系,能够与乙酰二
甲酸二甲酯和
丙炔酸乙酯发生高效和区域选择性环加成反应,分别生成螺[
咪唑-2,3â²-
噻吩]和螺[
咪唑-2,3â²-
吡咯]衍
生物,收率良好甚至极佳。