Ferrocenylimine Palladium (II) Complexes: Synthesis, Characterization and Application in Mizoroki-Heck and Suzuki-Miyaura Cross-Coupling Reactions

Carbon-carbon cross-coupling reactions are essential synthetic tools for synthesizing polymers, natural products, agrochemicals, and pharmaceuticals. Therefore, new catalysts that function with greater efficiency functional group tolerance being researched. We have prepared ferrocenylimine monodentate N P donor ligands N^N N^P bidentate chelating (L1 to L4) employed in stabilizing palladium ions application Mizoroki-Heck Suzuki-Miyaura reactions. The were successfully synthesized by Schiff base condensation of acetyl ferrocene hydrazine monohydrate afford ferrocenyl hydrazone (L1). Ligand L1 was further treated aldehydes give ferrocenyl(2-diphenylphosphino)imine (L3) ferrocenyl(pyridyl)imine (L3), while phosphination chlorodiphenylphosphine afforded L2. used prepare palladium(II) complexes (C1 C4) complexation [PdCl2(MeCN)2]. All the fully characterized using standard spectroscopic analytical techniques, including 1H NMR 13C spectroscopy, FT-IR mass spectrometry elemental analysis. tested efficacies catalyzing C-C proved be suitable catalyst precursors. Ferrocenyl(2-diphenylphosphine)imino ferrocenyl-methyl C2 C3 showed best activities at TONs up 201. (pre)catalysts demonstrated moderate activity involving substrates substituents on olefin aryl halide (including 4-Cl, 4-CH3, -CO2Me -CO2Et). Density Functional Theory study mechanism led confirmation widely accepted catalytic cycle. Catalyst precursors also displayed good selectivity reactions, 0.5 mol% loading, groups present boronic acid (such as 4-CHO, 4-COOH, 3-NO2, 3,5-dimethoxy 4-CH3).