Base-Catalyzed [3 + 2] Cycloaddition ofN-Benzyl Ketimines to Arylacetylenes Followed by Oxidation: A One-Pot Access to Polyarylated 2H-Pyrroles via Intermediate Pyrrolines

• DOI: 10.1021/acs.orglett.1c01009
• Publication Date: 2021-05-21T12:56:13Z
• Authors: Ivan A. Bidusenko; Elena Yu. Schmidt; Igor A. Ushakov; Alexander V. Vash...; Boris A. Trofimov
• Keywords: 01 natural sciences; 0104 chemical sciences

N-Benzyl ketimines undergo [3 + 2] cycloaddition with arylacetylenes in the KOBut/DMSO solution to 2,3,5-triarylpyrrolines, which are oxidized (chloranil, DDQ) in situ to 2,3,5-triaryl-2H-pyrroles in 53-71% yields. The intermediate 1-pyrrolines can be isolated in 31-91% yields and separately oxidized to the corresponding 2H-pyrroles.