Activation of CH bonds of imines by ruthenium compounds

Abstract

The synthesis of different Schiff’s bases has been described in order to use them as ligand for the subsequent cyclometallation reaction. The cyclometallation reaction has been described starting with a half sandwich ruthenium complex, [RuCl2(p-cymene)2]2, and different benzylimines via ortho – CH activation. The reaction takes place at room temperature in methanol and in a short period of time (4 hours), using 2 equivalents of potassium acetate as deprotonation agent. This cyclometallation reaction leads the endo cyclometallated ruthenium product. The resultant N – Ru – C metallocycle compound is formed by a five-member ring containing the C = N bond. The molecular structures of each compound have been characterised by different spectroscopic techniques (IR, NMR and Mass) showing that the obtained product is in agreement with the proposed structures.