title: Efficient Benzimidazolidinone Synthesis via Rhodium-Catalyzed Double-Decarbonylative C-C Activation/Cycloaddition between Isatins and Isocyanates.
abstract: The first decarbonylative cycloaddition of less-strained cyclic ketones (isatins) with isocyanates is reported. Initiated by C-C activation, this distinct [5-2+2] transformation provides a rapid entry to access various benzimidazolidinone derivatives, through which a wide range of isocyanates can be efficiently coupled with broad functional group tolerance. A modified one-pot process, combining Curtius rearrangement and C-C activation, was also achieved by using acyl azides as the starting materials. Detailed mechanistic study revealed a surprising double-decarbonylative reaction pathway. The novel reactivity discovered in this basic research is expected to shed light on developing new heterocycle formation methods through a C-C/isocyanate coupling.
authors.affiliation: Department of Chemistry, University of Texas at Austin, Austin, Texas, 78712, USA.
authors.forename: Rong
authors.initials: R
authors.lastname: Zeng
authors.affiliation: Department of Chemistry, University of Texas at Austin, Austin, Texas, 78712, USA.
authors.forename: Peng-Hao
authors.initials: PH
authors.lastname: Chen
authors.affiliation: Department of Chemistry, University of Texas at Austin, Austin, Texas, 78712, USA.
authors.forename: Guangbin
authors.initials: G
authors.lastname: Dong
keywords: C–C activation; cycloaddition; isatin; isocyanate; rhodium