美国加州理工学院Sarah E. Reisman团队报道了Sm^III -醇酮质子解实现还原钐(电)催化。相关研究成果于2024年8月23日发表在《科学》。

二碘化钐（SmI₂）是一种特殊的单电子还原剂，可用于各种合成环境。然而，由于与切割强Sm^III-O键相关的众所周知的挑战，催化转换的通用方法仍然难以捉摸。之前的研究主要集中在使用高反应性亲氧体来实现催化剂的周转。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。

该文中，研究人员利用温和和选择性的且范围广泛的质子醇解策略，实现了钐催化的酮和丙烯酸酯的分子间还原性交叉偶联。该方法的模块化使基于溶剂、pKa（其中Ka是酸离解常数）和钐配位范围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提供了基础。

附：英文原文

Title: Reductive samarium (electro)catalysis enabled by SmIII-alkoxide protonolysis

Author: Emily A. Boyd, Chungkeun Shin, David J. Charboneau, Jonas C. Peters, Sarah E. Reisman

Issue&Volume: 2024-08-23

Abstract: Samarium diiodide (SmI2) 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 SmIII–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, pKa (where Ka is the acid dissociation constant), and the samarium coordination sphere and provides a basis for future developments in catalytic and electrocatalytic lanthanide chemistry.

DOI: adp5777

Source: https://www.science.org/doi/10.1126/science.adp5777