Metal-free regioselective strategy for the synthesis of 2-nitro-3-arylimidazo[1,2-a]pyridines from β-nitrostyrene and 2-aminopyridines under aerobic conditions using silica sulfuric acid (SSA) as heterogeneous catalyst has been developed. The synthetic methodology provides the title compounds with good yields under mild conditions, and complete regioselectivity is observed. Furthermore, SSA was not used previously for this transformation.

中文翻译：

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2-Nitro-3-arylimidazo[1,2-的无金属区域选择性合成

已经开发了在有氧条件下使用二氧化硅硫酸 (SSA) 作为非均相催化剂从 β-硝基苯乙烯和 2-氨基吡啶合成 2-硝基-3-芳基咪唑并[1,2- a ]吡啶的无金属区域选择性策略。合成方法在温和条件下提供了具有良好收率的标题化合物，并且观察到了完全的区域选择性。此外，先前未将 SSA 用于此转换。