Performing reactions in the solid state offers the largely unexplored possibility of influencing reactivity by manipulating the solid form of the starting reactants. In this work, we explore the use of various solid forms of barbituric acid and its effect on reaction paths and kinetics in a Knoevenagel condensation reaction with vanillin. Modifications of barbituric acid included the use of its desmotrope, a cocrystal, and a salt as the starting reactant. Comparing these reactions with the reaction starting from the commercial keto tautomer of barbituric acid, we find that the reaction kinetics could be accelerated or decelerated, together with a change in the reaction mechanism. Exploring solid forms of reactants can be used as general methodology for manipulating mechanochemical reactivity, further highlighting the benefits of conducting reactions in the solid state, because many of the modifications of solids become unavailable upon dissolution.

中文翻译：

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使用 Desmotropes、共晶和盐来控制机械化学有机反应中的反应性

在固态下进行反应提供了通过操纵起始反应物的固体形式来影响反应性的很大程度上未开发的可能性。在这项工作中，我们探索了各种固体形式的巴比妥酸的使用及其对 Knoevenagel 与香草醛缩合反应中反应路径和动力学的影响。巴比妥酸的改性包括使用其去氢键、共晶和盐作为起始反应物。将这些反应与从巴比妥酸的商业酮互变异构体开始的反应进行比较，我们发现反应动力学可以加速或减速，同时反应机制也会发生变化。探索反应物的固体形式可用作操纵机械化学反应性的一般方法，