Department of Chemistry, Center for Molecular Innovation and Drug Discovery, Chemistry of Life Processes Institute, Silverman Hall, Northwestern University, Evanston, IL, 60208, (USA).
Angew Chem Int Ed Engl. 2016 Nov 21;55(48):14912-14922. doi: 10.1002/anie.201605319. Epub 2016 Oct 20.
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.
氮杂环卡宾（NHC）催化已成为有机合成中构建复杂分子的一种强大策略，主要通过极性反转（umpolung）方法实现。这些独特的路易斯碱已被用于催化方式产生酰基阴离子、烯醇盐和同烯醇盐。最近，出现了一种新策略，通过利用额外的激活模式——协同催化，极大地扩展了卡宾催化的合成实用性。仔细选择和平衡共催化剂导致了反应性的增强、产率的提高和立体选择性的改善。在某些情况下，这些催化添加剂改变了区域选择性或非对映选择性。这篇综述强调了 NHC 协同催化的新进展，并调查了该领域的发展。
