Complex compounds of a series of d metals with rubazinic acid (HRub). Crystal and molecular structure of [Co(H2O)6](NO 3)2 • 2HRub

Seven complexes of d elements with rubazinic acid, (4Z)-4-[(5-hydroxy-1,3- dimethyl-1H-pyrazol-4-yl)imino]-2,5-dimethyl-2,4-dihydro-3H-pyrazol-3-one (HRub), were synthesized and studied by IR and UV/Vis spectroscopy and potentiometry. The composition of the complexes in solution was determined by spectrophotometry and their stability constants were calculated. The crystal and molecular structures of [Co(H2O)6](NO3) 2 • 2HRub were determined by X-ray diffraction. © 2010 Pleiades Publishing, Ltd.