N-Heterocyclic Carbenes: Organocatalysts Displaying Diverse Modes of Action
Within the context of Lewis base catalysis N-heterocyclic carbenes represent an extremely versatile class of organocatalyst that allows for a great variety of different transformations. Starting from the early investigations on benzoin, and later Stetter reactions, the mechanistic diversity of N-heterocyclic carbenes, depending on their properties, has led to the development of several unprecedented catalytic reactions. This article will provide an overview of the versatile reactivity of N-heterocyclic carbenes.
KeywordsRing Opening Polymerization Alder Reaction Aldol Reaction Imidazolium Salt Chloro Acetylchloride
Generous financial support by the Deutsche Forschungsgemeinschaft (DFG priority program SPP1179 ‘organocatalysis’) and by the Fonds der Chemischen Industrie (Liebig fellowship) is gratefully acknowledged.
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