This review is devoted to the scientific achievements of the departments of organic chemistry in higher schools of Russia within the past decade.

In the title compound, [Cu(C₂₁H₁₉N₆O₂)Cl], the Cu^IIatom is in a slightly distorted square-planar coordination involving two O atoms from the pyrazolone rings [Cu—O = 2.088 (10) and 1.975 (10) Å], an N atom of the azo group [Cu—N = 2.048 (13) Å] and a chloride anion [Cu—Cl = 2.183 (5) Å]. The organic anions act as tridentate chelating ligands. The molecules stack in columns along thecaxis.