Aryne-Based Multicomponent Coupling Reactions

Multicomponent reactions (MCRs) constitute a powerful synthetic tool to generate a large number of small molecules with high atom economy, which thus can efficiently expand the chemical space with molecular diversity and complexity. Aryne-based MCRs offer versatile possibilities to construct functionalized arenes and benzo-fused heterocycles. Because of their electrophilic nature, arynes couple with a broad range of nucleophiles. Thus, a variety of aryne-based MCRs have been developed, the representative of which are summarized in this account. 1 Introduction 2 Aryne-Based Multicomponent Reactions 2.1 Trapping with Isocyanides 2.2 Trapping with Imines 2.3 Trapping with Amines 2.4 Insertion into π-Bonds 2.5 Trapping with Ethers and Thioethers 2.6 Trapping with Carbanions 2.7 Transition-Metal-Catalyzed Approaches 3 Strategies Based on Hexadehydro Diels–Alder Reaction 3.1 Dihalogenation 3.2 Halohydroxylation and Haloacylation 3.3 Amides and Imides 3.4 Quinazolines 3.5 Benzocyclobutene-1,2-diimines and 3H-Indole-3-imines 3.6 Other MCRs of Arynes and Isocyanides 4 Conclusion