Effect of the solvent nature and the number of electrophilic substituents in the molecule on hydration of nitro derivatives of phenanthrene-9,10-quinone

Solvates (1 : 2) of 10,10-dihydroxy-2,4,7-trinitro-9,10-dihydrophenanthren- 9-one with DMSO and of 10,10-dihydroxy-2,7-dinitro-9,10-dihydrophenanthren- 9-one with HMPA were prepared. The crystal structure of 2,5-dinitrophenanth rene-9,10-quinone was established. The results of X-ray diffraction analysi s and IR spectroscopy of a series of mono-, di-, and trinitro derivatives o f phenanthrene-9,10-quinone demonstrated that the ability of carbonyl group s to participate in nucleophilic addition of water increases as the number of nitro groups in substituted phenanthrene-9,10-quinone increases. The nat ure of the solvent (HMPA, DMF, or DMSO) affects hydration of phenanthrenequ inones primarily due to the difference in the strength of intermolecular hy drogen bonds stabilizing di- and tetrahydroxy-dihydrophenanthrenes.