High reactivity of the Schiff base product of p-toluidine with pyridine-2-carboxaldehyde was observed, leading to methyl group isomerization (immigration) to ortho-position followed by the dimerization reaction to form biphenyl system. This compound was identified and characterized using Infra-red (IR), Electrospray Ionization (ESI) Mass Spectra (MS) and Nuclear Magnetic Resonance (NMR) spectroscopic methods and its structure confirmed by XRD single crystal. Reaction mechanism was proposed in view of similar reactions. The coordination behavior of the Schiff base was examined against many metal salts and some organometallic centers. Two metal complexes were only isolated and identified by X-ray crystallography for ruthenium (II) and zinc (II). The coordination behavior of both metals differs significantly, although both of them promote the oxidation reaction on one of the azomethine bond.