Pd-PEPPSI complexes based on 1,2,4-triazol-3-ylidene ligands as efficient catalysts in the Suzuki-Miyaura reaction

The palladium complexes of the Pd-PEPPSI type with N-heterocyclic carbenes of the 1,2,4-triazole series were synthesized in 76—99% yields by the reactions of PdCl₂ with 1,4-di- alkyl-1,2,4-triazolium salts in pyridine in the presence of KBr or KI as sources of halide ions and tetrabutylammonium salts as phase-transfer catalysts. The obtained complexes can be used as efficient catalysts for the Suzuki—Miyaura cross-coupling and are not inferior to the commercially available Pd-PEPPSI catalysts in activity.