Fricke Christoph, Sperger Theresa, Mendel Marvin, Schoenebeck Franziska
Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany.
Angew Chem Int Ed Engl. 2021 Feb 15;60(7):3355-3366. doi: 10.1002/anie.202011825. Epub 2020 Dec 10.
Dinuclear Pd complexes have found widespread applications as diverse catalysts for a multitude of transformations. Initially their ability to function as pre-catalysts for low-coordinated Pd species was harnessed in cross-coupling. Such Pd dimers are inherently labile and relatively sensitive to oxygen. In recent years, more stable dinuclear Pd -Pd frameworks, which feature bench-stability and robustness towards nucleophiles as well as recoverability in reactions, were explored and shown to trigger privileged reactivities via dinuclear catalysis. This includes the predictable and substrate-independent, selective C-C and C-heteroatom bond formations of poly(pseudo)halogenated arenes as well as couplings of arenes with relatively weak nucleophiles, which would not engage in Pd /Pd catalysis. This Minireview highlights the use of dinuclear Pd complexes as both pre-catalysts for the formation of highly active Pd and Pd -H species as well as direct dinuclear catalysts. Focus is set on the mechanistic intricacies, the speciation and the impacts on reactivity.
双核钯配合物作为多种转化反应的不同催化剂已得到广泛应用。最初，它们作为低配位钯物种的前催化剂在交叉偶联反应中的功能得到了利用。这类钯二聚体本质上不稳定，对氧气相对敏感。近年来，人们探索了更稳定的双核钯-钯骨架，其具有在实验台上的稳定性、对亲核试剂的耐受性以及在反应中的可回收性，并表明它们可通过双核催化引发特殊的反应活性。这包括聚（伪）卤代芳烃可预测且与底物无关的选择性碳-碳和碳-杂原子键形成，以及芳烃与相对较弱亲核试剂的偶联反应，而这些反应不会参与钯/钯催化。本综述重点介绍了双核钯配合物作为形成高活性钯和钯-氢物种的前催化剂以及直接双核催化剂的应用。重点关注其复杂的机理、物种形成以及对反应活性的影响。
