(Sulfasalazinato-κO)bis(triphenylphosphine-κP)copper(I)

The title mixed-ligand copper(I) complex, [Cu(C(18)H(13)N(4)O(5)S)-(C(18)H(15)P)(2)], was synthesized via solvothermal reaction of [Cu(PPh(3))(2)(MeCN)(2)]ClO(4) and sulfasalazine [systematic name: 2-hydroxy-5-(2-{4-[(2-pyridylamino)sulfonyl]phenyl}diazenyl) benzoic acid]. The mononuclear complex displays a trigonal coordination geometry for the Cu(I) atom, which is surrounded by two P-atom donors from two different PPh3 ligands and one O-atom donor from the monodentate carboxylate group of the sulfasalazinate ligand. The latter ligand is found in a zwitterionic form, with a deprotonated amine N atom and a protonated pyridine N atom. Such a feature was previously described for free sulfasalazine. The crystal structure is stabilized by C-H center dot center dot center dot O, C-H center dot center dot center dot N, N-H center dot center dot center dot N and O-H center dot center dot center dot O hydrogen bonds.