SmI₂ was introduced to organic chemistry as a single electron transfer agent in 1977. After ca. 15 years of latency, the scientific community has realized the high potential of this reagent, and its chemistry has started blooming. This versatile reagent has mediated a myriad of new bond formations, cyclizations, and other reactions. Its popularity stems largely from the fact that three different intermediates, radical anions, radicals, and anions, depending on the ligand or additive used, could be obtained. Each of these intermediates could in principle lead to a different product. While these options vastly enrich the repertoire of SmI₂, they necessitate a thorough mechanistic understanding, especially concerning how appropriate ligands direct the SmI₂ to the desired intermediate. Our first paper on this subject dealt with the reduction of an activated double bond. The results were puzzling, especially the H/D isotope effect, which depended on the order of the reagents addition. This seminal paper was fundamental to an understanding of how the SmI₂ works and enabled us to later explain various phenomena. For example, it was found that in a given reaction, when MeOH is used as a proton source, a spiro compound is obtained, while a bicyclic product is obtained when t-BuOH is used. Our contribution culminated in formulating guidelines for the rational use of proton donors in SmI₂ reactions.

中文翻译：

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mar碘化物展示柜：揭示机理难题

1977年，SmI ₂作为单电子转移剂被引入有机化学领域。经过15年的潜伏期，科学界已经意识到这种试剂的巨大潜力，其化学作用也开始蓬勃发展。这种多功能试剂介导了许多新的键形成，环化和其他反应。它的流行主要是由于可以获得三种不同的中间体，自由基阴离子，自由基和阴离子，这取决于所使用的配体或添加剂。这些中间体中的每一种原则上都可以产生不同的产物。尽管这些选择极大地丰富了SmI _2的功能，但它们仍需要全面的机理理解，尤其是有关合适的配体如何引导SmI _{2的知识。}到所需的中间体。关于该主题的第一篇论文涉及活化双键的还原。结果令人费解，尤其是H / D同位素效应，这取决于试剂添加的顺序。这篇开创性的论文对于理解SmI _2的工作原理至关重要，使我们能够在以后解释各种现象。例如，发现在给定的反应中，当使用MeOH作为质子源时，获得螺环化合物，而当使用t- BuOH时，获得双环产物。我们的贡献最终形成了在SmI ₂反应中合理使用质子供体的指导方针。