N,N-Diethyl­anilinium 5-(2,4-dinitro­phen­yl)-2,6-dioxo-1,2,3,6-tetra­hydro­pyrimidin-4-olate

The asymmetric unit of the title mol­ecular salt, C₁₀H₁₆N⁺·C₁₀H₅N₄O₇⁻ (trivial name: N,N-diethyl­anilinium 2,4-dinitro­phenyl­barbiturate), comprises two anion–cation units. In the anions, the dinitro­phenyl ring and the mean plane of the barbiturate ring [planar to within 0.011 (2) and 0.023 (2) Å in the two anions] are inclined to one another by 41.47 (9) and 45.12 (9)°. In the crystal, the anions are linked via strong N—H...O hydrogen bonds, forming chains propagating along [10-1]. Within the chains, adjacent inversion-related anionic barbiturate entities are joined through R₂²(8) ring motifs. The cations are linked to the chains via N—H...O hydrogen bonds. The chains are linked via a number of C—H...O inter­actions, forming a three-dimensional structure.

N,N-Diethyl­anilinium 5-(5-chloro-2,4-dinitro­phen­yl)-2,6-dioxo-1,2,3,6-tetra­hydro­pyrimidin-4-olate

In the anion of the title salt, C₁₀H₁₆N⁺·C₁₀H₄ClN₄O₇⁻ [trivial name = N,N-diethyl­anilinium 5-(3-chloro-4,6,-dinitro­phen­yl)barbiturate], the dihedral angle between the benzene and pyrimidine rings is 45.49 (6)°. The mean plane of the nitro group, which is ortho-substituted with respect to the pyrimidine ring, is twisted by 41.57 (13)° from the benzene ring, while the mean plane of the nitro group, which is para-substituted, is twisted by 14.41 (12)° from this ring. In the crystal, N—H...O hydrogen bonds link cations and anions into chains along [1-10]. Within the chains, inversion-related anionic barbiturate anions form R₂²(8) ring motifs.

Trimethyl­ammonium 5-(2,4-dinitro­phenyl)-2,6-dioxo-1,2,3,6-tetra­hydro­pyrimidin-4-olate 0.125-hydrate

The asymmetric unit of the title salt C₃H₁₀N⁺·C₁₀H₅N₄O₇⁻·0.125H₂O [trivial name: trimethyl­ammonium 5-(2,4-dinitro­phen­yl)barbiturate 0.125-hydrate], contains two independent cations, two independent anions and a 0.25-occupancy solvent water mol­ecule. In one of the cations, the C atoms are disordered over two sets of sites with refined occupancies of 0.538 (8) and 0.462 (8). In the anions, the dihedral angles between the pyrimidine and benzene rings are 42.77 (6) and 46.55 (7)°. In the crystal, N—H...O hydrogen bonds connect anions and cations into chains along [010]. Within these chains, R₂²(8) ring motifs are formed by inversion-related barbiturate anions. The H atoms of the partial occupancy water mol­ecule were not located nor included in the refinement.

1,2-Bis(2,4-di­nitro­phen­yl)disulfane

In the title mol­ecule, C₁₂H₆N₄O₈S₂, the dihedral angle between the benzene rings is 77.00 (8)°. The mean planes of the nitro groups are twisted slightly from the benzene rings, forming dihedral angles in the range 2.3 (2)–8.6 (3)°. The S—S bond length is 2.0458 (7) Å. Each S atom is essentially coplanar with the benzene ring to which it is attached, with deviations from the ring planes of 0.0163 (5) and 0.0538 (5) Å. In the crystal, mol­ecules are linked through weak C—H...O hydrogen bonds, forming a two-dimensional network parallel to (001).

N,N-Diethyl-2-hy­droxy­ethanaminium 5-(2,4-di­nitro­phen­yl)barbiturate sesquihydrate

In the title hydrated mol­ecular salt, C₆H₁₆NO⁺·C₁₀H₅N₄O₇⁻·1.5H₂O [systematic name: N,N-diethyl-2-hy­droxy­ethan­am­in­ium 5-(2,4-di­nitro­phen­yl)-2,6-di­oxo-1,2,3,6-tetra­hydro­pyrim­idin-4-olate sesquihydrate], the dihedral angle between the six-membered rings in the anion is 37.66 (11)°. The nitro groups ortho and para to the ring junction are rotated from their attached ring by 40.8 (3) and 23.5 (3)°, respectively. The ethanol group is disordered over two of the `arms' of the cation in a statistical ratio. In the crystal, [010] chains of anions occur, linked by N—H...O and O—H...O hydrogen bonds, which generate R₂²(8) loops. Further N—H...O and O—H...O hydrogen bonds link the components into a three-dimensional network. One of the water O atoms lies near an inversion centre and is 50% occupied.