A Unified Approach for Divergent Synthesis of Heterocycles <i>via</i> TMSOTf‐Catalyzed Formal [3+2] Cycloaddition of Electron‐Rich Alkynes
Ping Chen, Wei Cao, Xiangqian Li, Dayong Shi
Abstract
Abstract We present a synthetic protocol for the construction of polysubstituted five‐membered heterocycles via TMSOTf‐catalyzed formal [3+2] cycloaddition of electron‐rich alkynes, which features free from any metal, atom economy and water as the main by‐product. Furthermore, alkenyl ether adduct has been verified as the key intermediate. Notably, by utilizing this approach, we can synthesize a broad range of polysubstituted furans, thiophenes and pyrroles, and extend this transformation to deliver fused‐polyheterocycles. This reaction can be achieved on a gram scale and the corresponding products are intermediates for producing diverse potentially useful scaffolds. magnified image
Topics & Concepts
ChemistryCycloadditionCatalysisFormal synthesisCombinatorial chemistryAdductAtom economyOrganic chemistryCatalytic C–H Functionalization MethodsCatalytic Alkyne ReactionsSynthesis and Characterization of Pyrroles