New monoclinic form of {O-Ethyl N-(4-nitrophenyl)thiocarbamato-κS}(tri-4-tolylphosphane-κP)gold(I): crystal structure and Hirshfeld surface analysis

The title phosphanegold(I) thiolate compound, [Au(C9H9N2O3S)(C21H21P)], is a second monoclinic polymorph (space group P21/c) that complements a previously reported Cc polymorph [Broker & Tiekink (2008). Acta Cryst. E64, m1582]. An SP donor set defines an approximately linear geometry about the gold atom in both forms. The key distinguishing feature between the present structure and the previously reported polymorph rests with the relative disposition of the thiolate ligand. In the title compound, the orientation is such to place the oxygen atom in close contact with the gold atom [Au...O = 2.915 (2) Å], in contrast to the aryl ring in the original polymorph. In the crystal, linear supramolecular chains along the a-axis direction mediated by C–H...π and nitro-O...π interactions are found. These pack with no directional interactions between them. The analysis of the Hirshfeld surfaces for both forms of [Au(C9H9N3O3S)(C21H21P)] indicates quite distinctive interaction profiles relating to the differences in intermolecular contacts found in their respective crystals.