We have prepared substituted flexible dimeric pyridinium bromide using conventional and greener approach. Solvent-free solid phase (greener) approach is superior than the conventional owing to nontoxic, easy workup procedure, and 20 times lesser reaction time. Toxic organic solvents and column chromatography are avoided. Aldol condensation reaction is studied with various substituted aromatic aldehyde and compared with available recent literatures. Synthesized substituted flexible dimeric pyridinium salts acted as potential catalysts because of their better performance even in low concentration, recyclability, and activation of two molecules of aldehydes at the same time for aldol condensation reaction.

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制备取代的柔性二聚吡啶鎓盐的绿色合成方法及其重要性

我们使用传统和更环保的方法制备了取代的柔性二聚溴化吡啶。无溶剂固相（更环保）方法优于传统方法，因为它无毒、易于处理，反应时间缩短 20 倍。避免使用有毒有机溶剂和柱色谱法。用各种取代的芳香醛研究了羟醛缩合反应，并与可用的最新文献进行了比较。合成的取代柔性二聚吡啶鎓盐即使在低浓度下也具有更好的性能、可回收性和同时活化两分子醛进行羟醛缩合反应，因此它们可作为潜在的催化剂。