Advances in Catalysis: Catalytic Efficiencies Of Palladium (II) Complexes on Suzuki-Miyaura Cross Couplings

Authors: 1Oloyede, H.O.; 1Obijole, O.A; 1Fehintola, E.O.; 2Sabejeje, A.J.; 1Akinlami, O.O; 1Ojo, B.M. and 1Omodara, N.B.
1 Chemistry Dept. ACE, Ondo
2 Integrated Science Dept. ACE, Ondo

Series of dichloropalladium (II) complexes based on derivatives of moderately electron-donating {(5-methylthiophen-2-yl) methylene} aniline ligands were synthesized and characterized. The ligands are N^S donor systems with different structural/electronic substituents. Of all the ligands synthesized, only one forms solid product. Therefore, there was necessity to employ the method of in situ synthesis of the palladium (II) complexes (Scheme 1). The complexes were used as pre-catalysts for high temperature Suzuki-Miyaura cross-coupling reaction in order to evaluate the catalytic efficiencies of the preformed complexes. The catalysis result indicated that the pre-catalyst have higher catalyst efficiencies towards arylhalide substrate with electron-releasing substituents. This result suggests a higher electrophilicity of the palladium metal centres which further indicates that the ligand backbones are generally weak electron donors.

Keywords: Palladium (II), complexes, in situ, catalysts, cross-couplings, Suzuki-Miyaura