title: Cooperative Catalysis and Activation with N-Heterocyclic Carbenes.
abstract: N-Heterocyclic carbene (NHC) catalysis has emerged as a powerful stratagem in organic synthesis to construct complex molecules primarily by polarity reversal (umpolung) approaches. These unique Lewis bases have been used to generate acyl anions, enolates, and homoenolates in catalytic fashion. Recently, a new strategy has emerged that dramatically expands the synthetic utility of carbene catalysis by leveraging additional activation modes: cooperative catalysis. The careful selection and balance of cocatalysts have led to enhanced reactivity, increased yields, and improved stereoselectivity. In certain cases, these catalytic additives have changed the regioselectivity or diastereoselectivity. This Minireview highlights new advances in NHC cooperative catalysis and surveys the evolution of this field.
authors.affiliation: Department of Chemistry, Center for Molecular Innovation and Drug Discovery, Chemistry of Life Processes Institute, Silverman Hall, Northwestern University, Evanston, IL, 60208, (USA).
authors.forename: Michael H
authors.initials: MH
authors.lastname: Wang
authors.affiliation: Department of Chemistry, Center for Molecular Innovation and Drug Discovery, Chemistry of Life Processes Institute, Silverman Hall, Northwestern University, Evanston, IL, 60208, (USA).
authors.forename: Karl A
authors.initials: KA
authors.lastname: Scheidt
mesh_terms: D002384:Catalysis; D006571:Heterocyclic Compounds / Q000737:chemistry*; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D006571:Heterocyclic Compounds; C030011:carbene; D008697:Methane
keywords: N-heterocyclic carbenes; cooperative catalysis; organocatalysis; synthetic methods