AgI‐Catalyzed Reaction of Enol Diazoacetates and Imino Ethers: Synthesis of Highly Functionalized Pyrroles. (6th May 2021)

• Record Type: Journal Article
• Authors: Dong, Kuiyong; Humeidi, Ahmad; Griffith, Wendell; Arman, Hadi; Xu, Xinfang; Doyle, Michael P.
• Is Part Of: Angewandte Chemie. Volume 133:Number 24(2021)
• Page Start: 13506
• Page End: 13512
• Publication Date: 2021-05-06
• Subjects: [3+2]-cycloaddition -- C−O cleavage -- enodiazo compounds -- imino ether -- pyrroles; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202101641
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: An unprecedented Ag I ‐catalyzed efficient method for the coupling of imino ethers and enol diazoacetates through a [3+2]‐cycloaddition/C−O bond cleavage/[1, 5]‐proton transfer cascade process is reported. The general class of imino ethers that includes oxazolines, benzoxazoles and benzimidates are applicable substrates for these reactions that provide direct access to fully substituted pyrroles with uniformly high chemo‐ and regioselectivity. High variability in substitution at the pyrrole 2‐, 5‐ and N‐positions characterizes this methodology that also presents an entry point for further pyrrole diversification via facile modification of resulting N‐functional pyrroles. Abstract : An efficient and novel Ag I ‐catalyzed methodology for the synthesis of multisubstituted 4‐silyloxypyrrole‐3‐carboxylates with broad variability for the placement of substituents at the 2, 5‐, and N‐positions is presented. Convenient conversion of imino ethers to fully substituted pyrroles with uniformly high chemo‐ and regioselectivity was achieved. Mechanistic studies confirm a [3+2]‐cycloaddition/C−O bond cleavage/ [1, 5]‐proton transfer cascade process.