Nickel (II) imidazol-2-ylidine Complexes Supported Through Internally Functionalized Amido Linkage Synthesis and Catalytic Studies for Suzuki Miyaura Cross Coupling

Reaction of various chloroacetamides with n-methyl imidazole afforded imidazolium salts of composition 1-methyl-3-N-(Ar)acetamido-1,3-imidazolium chloride (Ar = cyanophenyl, chlorophenyl, diphenyl). Treatment of latter prepared salts with NiCl₂.6H₂O in presence of excess K₂CO₃ yielded their respective complexes [{1-methyl-3-N-(Ar)acetamido-1,3-imidazol-2-ylidine}₂Ni] (Ar = p-cyanobenzene (2a), p-chlorobenzene (2b) and [{1-methyl-3-N-(diphenyl)acetamido-1,3-imidazol-2-ylidine}₂NiCl₂] (2c). All the synthesized complexes were characterized by IR, NMR (¹H, ¹³C{¹H}) spectroscopy and microanalysis. The molecular structure of complex [{1-methyl-3-N-(4-cyanophenyl)acetamido-1,3-imidazol-2-ylidine}₂Ni] 2a was established through single crystal-X-ray diffraction analysis. Subsequently, these complexes were studied as a catalyst for Suzuki Miyaura cross coupling reaction between 2-haloarene (halo = Cl, Br; arene = Ph, Nap, Py, Pym) and phenylboronic acid.