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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Sm III -醇盐原解实现的还原钐（电）催化


钐二碘化物 （SmI 2 ） 是一种用于多种合成环境中的特权单电子还原剂。然而，由于与裂解强 Sm III –O 键相关的众所周知的挑战，催化周转的通用方法仍然难以捉摸。之前的努力集中在使用高反应性嗜氧剂来实现催化剂周转。然而，这种方法会产生复杂的催化剂形态，并从本质上限制了合成范围。在此，我们利用温和和的选择性质子分解策略实现了钐催化的酮和丙烯酸酯的广泛分子间还原交叉偶联。我们方法的模块化允许基于溶剂 p Ka（其中 Ka 是酸解离常数）和钐配位球对选择性进行合理控制，并为催化和电催化镧系元素化学的未来发展奠定了基础。