Gutiérrez-Hernández Abelardo, Soto-Suárez Fátima M, Richaud Arlette, Méndez Francisco, Contreras-Celedón Claudia Araceli
Departamento de Síntesis Orgánica, Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia 58030, Mexico.
CEMHTI-CNRS, 45100 Orléans, France.
Molecules. 2024 Nov 15;29(22):5381. doi: 10.3390/molecules29225381.
The use of deep eutectic solvents (DESs) as catalysts presents indisputable advantages, for example, their simplicity of preparation, high biodegradability, and recyclability, as well as zero toxicity and their effectiveness as environmentally friendly reaction media. However, aspects related to their reactivity and catalytic activity are still unclear. In this work, we explore the versatility of ChCl/ZnCl DES in the formation of C-C bonds through the Michael-type addition of pyrrole to maleimide, where ChCl/ZnCl DES leads to catalysis and chelation of the substrates, thus describing a recommended method for the construction of C-C bonds with high atomic economy. We describe experimental and theoretical aspects that explain the ability of ChCl/ZnCl DES in the presence of water to act as a catalyst in the formation of C-C bonds between pyrrole and maleimide. The potential energy surface showed that the ChCl and the zinc-zincate species 2ZnCl·3HO, formed by the interaction between zinc chloride and water, decrease the relative free Gibbs energy values for all the species involved in the reaction mechanism (TSs, intermediates, product), favoring the kinetics and thermodynamics of the Michael addition.
使用深共熔溶剂（DESs）作为催化剂具有无可争议的优势，例如，其制备简单、高生物降解性、可回收性，以及零毒性和作为环境友好型反应介质的有效性。然而，与其反应性和催化活性相关的方面仍不清楚。在这项工作中，我们通过吡咯与马来酰亚胺的迈克尔型加成反应，探索了氯化胆碱/氯化锌DES在C-C键形成中的多功能性，其中氯化胆碱/氯化锌DES导致底物的催化和螯合作用，从而描述了一种具有高原子经济性的C-C键构建推荐方法。我们描述了实验和理论方面的内容，这些内容解释了在有水存在的情况下，氯化胆碱/氯化锌DES在吡咯与马来酰亚胺之间形成C-C键时作为催化剂的能力。势能面表明，由氯化锌与水相互作用形成的氯化胆碱和锌酸盐物种2ZnCl·3H₂O降低了反应机理中所有物种（过渡态、中间体、产物）的相对自由吉布斯能值，有利于迈克尔加成反应的动力学和热力学。
