Structure of (R,R)-4-bromo-2-{4-[4-bromo-1-(4-toluene-sulfon-yl)-1H-pyrrol-2-yl]-1,3-di-nitro-butan-2-yl}-1-(4-toluene-sulfon-yl)-1H-pyrrole, another ostensible by-product in the synthesis of geminal-dimethyl hydro-dipyrrins

The crystal structure of (R,R)-4-bromo-2-{4-[4-bromo-1-(4-toluene-sulfon-yl)-1H-pyrrol-2-yl]-1,3-di-nitro-butan-2-yl}-1-(4-toluene-sulfon-yl)-1H-pyrrole (1, C26H24Br2N4O8S2) is presented. The title compound was isolated in suitable yield as a by-product in our synthesis of geminal-dimethyl hydro-dipyrrins. We observe an unforeseen enanti-omeric resolution both in the bulk sample and the crystal of 1, with distinct C-H⋯O (Cmeth-yl-H⋯Onitro, Csp 3-H⋯Osulfon-yl) inter-actions observed in the enanti-omers present, along with other inter-actions, namely C5-pyrrol-yl-H⋯Osulfon-yl, forming a polymer along the crystallographic c-axis direction. Whilst pyrrolic fragments are well documented in the literature, little data is found surrounding the 1,3-di-nitro-butane scaffold.

Synthesis and structure determination of racemic (Δ/Λ)-tris-(ethyl-enedi-amine)-cobalt(III) trichloride hemi(hexa-aqua-sodium chloride)

In the racemic title compound, the [Co(en)₃]³⁺ and [Na(H₂O)₆]⁺cations exist in distorted octa­hedral coordination environments and charge neutrality in the salt is furnished by Cl⁻ anions. Structural cohesion is maintained by an array of C—H⋯O, N—H⋯Cl and O—H⋯Cl hydrogen bonds.

The synthesis and crystal structure of the title racemic compound, [Co(C₂H₈N₂)₃]Cl₃.{[Na(H₂O)₆]Cl}_0.5, are reported. The trivalent cobalt atom, which resides on a crystallographic threefold axis, is chelated by a single ethyl­ene di­amine (en) ligand and yields the tris-chelate [Co(en)₃]³⁺ cation with distorted octa­hedral geometry after the application of crystal symmetry. The sodium cation (site symmetry ), has a single water mol­ecule bound to it in the asymmetric unit and yields a distorted, octa­hedrally coordinated hydrated [Na(H₂O)₆]⁺ cation after the application of symmetry. One of the chloride ions lies on a general position and the other has site symmetry. An extensive array of C—H⋯O, N—H⋯Cl and O—H⋯Cl hydrogen bonds exists between the ethyl­ene di­amine ligands, the water mol­ecules of hydration, and the anions present, thereby furnishing solid-state stability.

Crystal structure of ethyl 2-methyl-5,10-dioxo-4-phenyl-5,10-di-hydro-4H-11-thia-1,4a-di-aza-benzo[b]fluorene-3-carb-oxy-late

The title compound, C24H18N2O4S, crystallizes in the ortho-rhom-bic P212121 space group, indicating the existence of only one enanti-omer with an S configuration of the chiral center in the crystal phase. The di-hydro-pyrimidine ring adopts a twist-boat conformation while the quinone ring is slightly non-planar. In the crystal, mol-ecules are linked by weak C-H⋯O and C-H⋯S hydrogen bonds and C-H⋯π inter-actions. In addition, a short inter-molecular S⋯N contact of 3.250 (3) Å indicates an inter-action between the S atom and the π-system of the thia-zole ring.