1. The 'weak base route' leading to transition metal–N-heterocyclic carbene complexes
- Author
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Catherine S. J. Cazin, Nikolaos V. Tzouras, Steven P. Nolan, Gianmarco Pisanò, and Ekaterina A. Martynova
- Subjects
STRUCTURAL-CHARACTERIZATION ,BISCARBENE COMPLEXES ,SUPPORTED PRECATALYSTS ,CATALYTIC-PROPERTIES ,Catalysis ,RUTHENIUM COMPLEXES ,chemistry.chemical_compound ,Transition metal ,Computational chemistry ,OXIDATIVE ADDITION ,PD-NHC NHC ,TRANSFER HYDROGENATION ,Materials Chemistry ,Organometallic chemistry ,Reaction conditions ,VERSATILE PRECATALYST ,Chemistry ,Metals and Alloys ,General Chemistry ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,ELECTRONIC-PROPERTIES ,Ceramics and Composites ,Weak base ,Carbene - Abstract
N-Heterocyclic carbenes (NHCs) are nowadays ubiquitous in organometallic chemistry and catalysis. Recently, a synthetic method which makes use of weak bases and desirable solvents has emerged as a simple, widely applicable and cost-effective pathway to well defined M-NHC complexes. Herein, recent studies devoted to the weak base approach are examined in detail, in order to showcase the simplicity, scope and variations of the method with regards to the azolium salts, bases and the metal sources, as well as the reaction conditions used. Mechanistic investigations are presented, illustrating the formation of intermediates which are air and moisture stable, prior to the metallation step. Finally, the importance, limitations and future prospects of the weak base route are discussed.
- Published
- 2021