Kaloglu, MuratKaloglu, NazanOzdemir, Ismail2024-08-042024-08-0420211011-372X1572-879Xhttps://doi.org/10.1007/s10562-021-03561-4https://hdl.handle.net/11616/99786The Pd-catalyzed direct arylation of pyrroles is an important research field for organic synthesis and catalysis chemistry. However, imidazolidin-2-ylidene based Pd-NHC complexes (NHC=N-heterocyclic carbene) have not yet been employed as catalysts for the direct C5 mono-arylation of C2-substituted N-methylpyrrole derivatives with aryl halides. Therefore, we now report the synthesis and characterization of new 1,3-bis(substituted benzyl) imidazolinium salts as carbene precursors, and their corresponding Pd-PEPPSI-NHC type complexes (PEPPSI=Pyridine Enhanced Precatalyst Preparation Stabilization and Initiation). The catalytic properties of these complexes have been evaluated in the direct C5 mono-arylation of N-methylpyrrole-2-carboxaldehyde with a wide variety of (hetero)aryl halides. This environmentally attractive procedure has also been found to be tolerant to a wide variety of functional groups on the aryl halides such as formyl, acetyl, nitrile, fluoro or trifluoromethyl, and good yields have been obtained in presence of 1 mol% catalyst loading at 120 degrees C. [GRAPHICS] .eninfo:eu-repo/semantics/closedAccessN-heterocyclic carbeneImidazolidin-2-ylidenePalladiumPEPPSI-type complexDirect arylationPyrroleArticle151113197321210.1007/s10562-021-03561-42-s2.0-85101527991Q2WOS:000621324600002Q3