Palladium complexes derived from benzoylthiourea ligands: Synthesis, crystal structure, and catalytic application in Suzuki C–C coupling reactions

Abstract

Abstract[PdCl2(HL1‐κS)2] and [PdCl2(HL2‐κS)2] complexes were formed from neutral monodentate modes of HL1 and HL2 ligands, which are coordinated to the palladium(II) center, respectively. [Pd(L1‐κ2S,O)2] and [Pd(L2‐κ2S,O)2] complexes were obtained by recrystallization of corresponding [PdCl2(HL1‐κS)2] and [PdCl2(HL2‐κS)2] complexes as anionic bidentate coordination modes. All palladium(II) complexes were characterized by elemental analysis, FT‐IR, and NMR (1H and 13C) techniques. The molecular structure of [Pd(L1‐κ2S,O)2] and [Pd(L2‐κ2S,O)2] was also confirmed by single‐crystal X‐ray diffraction method. The roles and behaviors of the prepared four palladium(II) complexes in catalytic investigations for the Suzuki C–C coupling reaction were examined for the first time. The complexes acted as the excellent catalyst precursor and showed highly catalytic activity for the Suzuki C–C coupling reaction of various arylhalides with phenylboronic acid at low catalyst loading (0.01 mol%).