2,2′-(Disulfanedi­yl)di­benzoic acid N,N-di­methyl­formamide monosolvate: crystal structure, Hirshfeld surface analysis and computational study

The title 1:1 solvate, C14H10O4S2·C3H7NO, features a twisted mol­ecule of 2,2′-di­thiodi­benzoic acid (DTBA), with the central C—S—S—C torsion angle being −88.57 (6)°, and a mol­ecule of di­methyl­formamide (DMF). The carb­oxy­lic acid groups are, respectively, close to co-planar and twisted with respect to the benzene rings to which they are connected as seen in the CO2/C6 torsion angles of 1.03 (19) and 7.4 (2)°. Intra­molecular, hypervalent S←O inter­actions are noted [S⋯O = 2.6140 (9) and 2.6827 (9) Å]. In the crystal, four-mol­ecule aggregates are formed via DTBA-O—H⋯O(DMF) and DTBA-O—H⋯O(DTBA) hydrogen bonding, the latter via an eight-membered {⋯OHCO}2 homosynthon. These are linked into supra­molecular layers parallel to (011) via benzene-C—H⋯O(DTBA) and DTBA-C=O⋯π(benzene) inter­actions, with the connections between these, giving rise to a three-dimensional architecture, being of the type benzene-C—H⋯π(benzene). An analysis of the calculated Hirshfeld surfaces indicates, in addition to the aforementioned inter­molecular contacts, the presence of stabilizing inter­actions between a benzene ring and a quasi-π-system defined by O—H⋯O hydrogen bonds between a DTBA dimer, i.e. the eight-membered {⋯OCOH}2 ring system, and between a benzene ring and a quasi-π(OCOH⋯OCH) system arising from the DTBA-O—H⋯O(DMF) hydrogen bond. The inter-centroid separations are 3.65 and 3.49 Å, respectively.