Synthesis and physicochemical properties of 9,10-phenanthrenequinone monoxime and its nitro derivatives

Phenanthrenequinone monoxime and its mono-, di-, and trinitro derivatives were synthesized. The acidity constants and their variation with the number and position of nitro groups were determined. The electronic and IR spectra of the nitro compounds were studied. The bands in the electronic spectra were assigned based on quantum-chemical calculations in the Pariser-Parr-Pople approximation. Correlations between the pKa values and some calculated characteristics of the compounds under study were found.