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Organized molecular systems as reaction media

机译：有组织的分子系统作为反应介质

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Media are among the most important factors to be considered for organic synthesis in soft and non-polluting conditions satisfying the conditions for sustainable development. Organized Molecular Systems (OMS) are very useful when efforts are being made to apply the twelve green chemistry principles, more precisely to replace organic solvents, to carry out reactions in water, to employ catalysis and biocatalysis, to economize molecules (and, of course, of atoms) and to work with low-energy conditions. These OMS posses a number of advantages: solubilization of substances that are not normally soluble in the continuous phase of OMS, localization of reactants and products, and selective orientation and stabilization of the various entities in the various stages of the reaction. Rapid and selective reactions of preparative amounts of substrate can be carried out in such media, which are also very suitable for mechanistic studies. First, we performed organic photoreactions in microemulsions (macroscopically homogeneous and transparent media). Thus, we were able to confirm the interfacial localization of the processes by means of chemical internal sensors and infrared spectroscopy; to propose a formulation strategy for diminishing the number of substrates in the medium (molecular economy principle); and to use high interfacial concentration to carry out reactions in the liquid phase although they are generally only possible in the solid state. The most important scientific point was the demonstration of the generalization of the amphiphilicity concept, by using polar non- aqueous solvents. 1986 saw the end of a controversy concerning the use of formamide in place of water. With this type of solvent, we have been able to perform important reactions: the Wacker process, Diels-Alder reactions, and olefin amidations. Then we postulated the formation of aggregates without surfactants if differential solvations were operative. All organic reactions can be influenced by the spontaneous formation of aggregates. To finish, with such systems, it is possible to orientate the reactivity of competitive reactions (e.g. cyclization and polymerization) and help to protect the environment, for example in the synthesis of clean surfactants in clean conditions. With the extension of these observations and results to the use of rigid objects (similar to rigid micelles) we were able to obtain very high enantioselective excess in chiral processes.
机译：在满足可持续发展条件的软性和无污染条件下，介质是有机合成应考虑的最重要因素。当努力应用十二种绿色化学原理，更确切地说是替代有机溶剂，在水中进行反应，利用催化和生物催化，节约分子（当然还有分子）时，有组织分子系统（OMS）非常有用。 ，原子）并在低能量条件下工作。这些OMS具有许多优点：溶解通常不溶于OMS连续相的物质，反应物和产物的定位以及反应各个阶段中各种实体的选择性取向和稳定化。制备量的底物的快速和选择性反应可以在这种介质中进行，这也非常适合于机理研究。首先，我们在微乳状液（宏观均匀和透明的介质）中进行了有机光反应。因此，我们能够通过化学内部传感器和红外光谱确定过程的界面定位。提出减少介质中底物数量的制定策略（分子经济原理）;尽管通常只能在固态下进行反应，但要使用高界面浓度在液相中进行反应。最重要的科学要点是通过使用极性非水溶剂来证明两亲性概念的普遍性。 1986年，有关使用甲酰胺代替水的争论结束了。使用这种类型的溶剂，我们能够进行重要的反应：Wacker工艺，Diels-Alder反应和烯烃酰胺化反应。然后假设如果不同的溶剂化作用有效，则无需表面活性剂就可形成聚集体。自发形成的聚集体会影响所有有机反应。最后，使用这样的系统，可以定向竞争性反应的反应性（例如环化和聚合反应）并帮助保护环境，例如在清洁条件下合成清洁的表面活性剂。通过将这些观察结果扩展到使用刚性物体（类似于刚性胶束），我们能够在手性过程中获得很高的对映选择性。

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