Palladium complexes derived from benzoylthiourea ligands: Synthesis, crystal structure, and catalytic application in Suzuki C–C coupling reactions
Ümmühan Solmaz, İlkay Gümüş, Mustafa Kemal Yılmaz, Simay İnce, Hakan Arslan
Abstract
Abstract [PdCl 2 (HL 1 ‐κS) 2 ] and [PdCl 2 (HL 2 ‐κS) 2 ] complexes were formed from neutral monodentate modes of HL 1 and HL 2 ligands, which are coordinated to the palladium(II) center, respectively. [Pd(L 1 ‐κ 2 S,O) 2 ] and [Pd(L 2 ‐κ 2 S,O) 2 ] complexes were obtained by recrystallization of corresponding [PdCl 2 (HL 1 ‐κS) 2 ] and [PdCl 2 (HL 2 ‐κS) 2 ] complexes as anionic bidentate coordination modes. All palladium(II) complexes were characterized by elemental analysis, FT‐IR, and NMR ( 1 H and 13 C) techniques. The molecular structure of [Pd(L 1 ‐κ 2 S,O) 2 ] and [Pd(L 2 ‐κ 2 S,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%).