Homo and hetero-bridged dinuclear copper(II) complex: Synthesis, X-ray structure and catalytic N-arylation

Two new dinuclear Cu(II) Schiff-base compounds have been synthesized and fully characterized. Reaction of CuCl2 with two slightly different polydentate Schiff-base ligands has afforded two different type of bridging of copper centers. While one is a simple dichloro-bridged compound, other one is a hetero-bridged (chloro and phenoxo oxygen) dinuclear compound. Both the compounds efficiently catalyzed N-arylation reaction of arylamines under homogeneous condition. [Display omitted] Two new dinuclear Cu(II) Schiff base compounds were synthesized, structurally characterized and their catalytic efficacy in N-arylation reaction was studied. Reaction of CuCl2 with two different polydentate Schiff base ligands viz. H2L1 (H2L1 = 1-(N-ortho-hydroxyacetophenimine)-ethane-2-ol) and H2L2 (H2L2 = 2-methoxy-6-[(2-hydroxyethylimino)methyl]phenol) has afforded two new very different in structure complexes [Cu2(HL1)2(µ-Cl)2]·(H2O)3 (1) and [Cu2L2(HL2)(µ-Cl)Cl]2·(H2O) (2). Complexes 1 and 2 were characterized by single crystal X-ray diffraction, FT-IR, elemental analysis, UV/Vis spectroscopic and TG/DTA studies. Complex 1 featured a simple dichloro-bridged dinuclear moiety, whereas 2 a hetero-bridged (chloro and phenolic oxygen) dinuclear compound. Catalytic efficacy towards N-arylation reactions between aryl iodide with aryl amine catalyzed by complexes 1 and 2 under homogeneous condition had been studied. Both the catalysts exhibited excellent catalytic efficacy in DMSO medium.