Samarium diiodide (SmI 2 ) is a privileged, single-electron reductant deployed in diverse synthetic settings. However, generalizable methods for catalytic turnover remain elusive because of the well-known challenge associated with cleaving strong Sm III –O bonds. Prior efforts have focused on the use of highly reactive oxophiles to enable catalyst turnover. However, such approaches give rise to complex catalyst speciation and intrinsically limit the synthetic scope. Herein, we leveraged a mild and selective protonolysis strategy to achieve samarium-catalyzed, intermolecular reductive cross-coupling of ketones and acrylates with broad scope. The modularity of our approach allows rational control of selectivity based on solvent, p K a (where K a is the acid dissociation constant), and the samarium coordination sphere and provides a basis for future developments in catalytic and electrocatalytic lanthanide chemistry.

中文翻译：

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通过 Sm III 醇盐质子分解实现还原钐（电）催化


二碘化钐 (SmI 2 ) 是一种独特的单电子还原剂，可用于多种合成环境。然而，由于与断裂强 Sm III -O 键相关的众所周知的挑战，催化转化的通用方法仍然难以捉摸。先前的努力集中在使用高反应性亲氧剂来实现催化剂的周转。然而，此类方法会产生复杂的催化剂形态并本质上限制了合成范围。在这里，我们利用温和的选择性质子解策略来实现钐催化的酮和丙烯酸酯的广泛范围的分子间还原交叉偶联。我们方法的模块化允许根据溶剂、pKa（其中Ka是酸解离常数）和钐配位层合理控制选择性，并为催化和电催化稀土化学的未来发展提供基础。