Pérez-García Pablo M, Sansores-Paredes María L G, Fonseca Guerra Célia, Vermeeren Pascal, Moret Marc-Etienne
Organic Chemistry and Catalysis, Institute for Sustainable and Circular Chemistry, Utrecht University, Universiteitsweg 99, 3584 CG, Utrecht, The Netherlands.
Universidad Privada Boliviana (UPB), Cochabamba, Bolivia.
Chemistry. 2024 Dec 5;30(68):e202403211. doi: 10.1002/chem.202403211. Epub 2024 Oct 23.
Nickel carbenes are key reactive intermediates in the catalytic cyclopropanation of olefins and other reactions, but isolated examples are scarce and generally rely on low coordination numbers (≤3) to stabilize the metal-ligand multiple bond. Here we report the isolation and characterization of a stable tetracoordinated nickel carbene bearing a triphosphine pincer ligand. Its nucleophilic character is evidenced by reaction with acids, and it can transfer the carbene fragment to CO to form a ketene. A computational study of the Ni=C chemical bond sheds light on the role of the third phosphine in the pincer framework to the stabilization of the nickel carbene fragment.
镍卡宾是烯烃催化环丙烷化反应及其他反应中的关键活性中间体，但分离得到的实例很少，且通常依赖低配位数（≤3）来稳定金属-配体多重键。在此，我们报告了一种带有三膦钳形配体的稳定四配位镍卡宾的分离与表征。它与酸反应证明了其亲核特性，并且它能将卡宾片段转移至CO以形成乙烯酮。对Ni=C化学键的计算研究揭示了钳形骨架中第三个膦对镍卡宾片段稳定性的作用。
