A mixed phosphine sulfide/selenide structure as an instructional example for how to evaluate the quality of a model

A sulfide/selenide solid-solution crystal structure is presented with an emphasis on model building and refinement. Some strategies and statistics for how to assess the accuracy of alternate models are described, including pitfalls, in the context of an instructional example that could be used as an activity in a classroom setting.

Crystal structure and Hirshfeld surface analysis of 2,5-di­imino-8a-methyl-4,9-bis­(4-methyl­phen­yl)-7-oxo-6-phenyl-deca­hydro-2H-3,8-methano­pyrano[3,2-c]pyridine-3,4a-dicarbo­nitrile N,N-di­methyl­formamide monosolvate

Inter­molecular C—H⋯O and C—H⋯N hydrogen bonds connect individual mol­ecules into layers extending parallel to (100). These layers are connected by C—H⋯π inter­actions.

Crystal structure of [2-({[2-(di­methylamino-κN)ethyl]imino-κN}methyl)phenolato-κO](1,10-phen­anthroline-κ²N,N′)copper(II) perchlorate

The asymmetric unit of the [Cu(L)(phen)](ClO₄) complex {L= 2-[(2-di­methyl­amino­ethyl­imino)­meth­yl]phenol} and phen = 1,10-phenanthroline) contains two crystallographically independent mol­ecules. It consists of alternating layers of he two types of mol­ecules, which stack along the c axis.

rac-1-(4-tert-Butyl­phen­yl)-5-ethyl-4-ferrocenyl-5-hy­droxy-1H-pyrrol-2(5H)-one

The title compound,which is produced by the oxidation of 1-(4-tert-butyl­phen­yl)-2-ethyl-3-ferrocenyl­pyrrole, crystallizes as a racemic mixture in the centrosymmetric space group P2₁/n. In the crystal, mol­ecules with the same absolute configuration are linked into infinite chains along the b-axis direction by O—H⋯O hydrogen bonds between the hy­droxy substituent and the carbonyl O atom of the adjacent mol­ecule.

Syntheses and crystal structures of three novel oxalate coordination compounds: Rb₂Co(C₂O₄)₂·4H₂O, Rb₂CoCl₂(C₂O₄) and K₂Li₂Cu(C₂O₄)₃·2H₂O

Rb₂Co(C₂O₄)₂·4H₂O consists of isolated [Co(C₂O₄)₂·2H₂O] octa­hedra which are connected only by hydrogen bonding of the water mol­ecules. Rb₂CoCl₂(C₂O₄) consists of chains of Co²⁺ cations connected via oxalate bridging ligands. In K₂Li₂Cu(C₂O₄)₃·2H₂O, the metal cations are inter­connected by oxalate ligands forming a novel three-periodic network.

Consistent zincophosphite 4-ring `ladder' chain structural motif with isomeric ligands

The same `ladder' chain motif built up from ZnO₃N and HPO₃ units arises for zincophosphites templated by isomers of 2-amino-z-methyl­pyridine (z = 3, 4, 5).

Synthesis and structure of 4-hy­droxy-N-iso­propyl­tryptamine (4-HO-NiPT) and its precursors

The synthesis of the norpsilocin derivative, 4-hy­droxy-N-iso­propyl­tryptamine, is presented, as well as its crystal structure and the structures of its three synthetic precursors.

Crystal structure and Hirshfeld surface analysis of 3-(3-hy­droxy­phen­yl)-1-(1H-pyrrol-2-yl)prop-2-en-1-one hemihydrate

3-(3-Hy­droxy­phen­yl)-1-(1H-pyrrol-2-yl)prop-2-en-1-one (3HPPP) crystallized as planar mol­ecule together with half a mol­ecule of water in the asymmetric unit in the monoclinic crystal system with space group P2/c. A Hirshfeld surface analysis for the chalcone component showed that H⋯H (40.9%) and H⋯C/C⋯H (32.4%) contacts make the largest contributions to the crystal packing of 3HPPP. In the vicinity of water, the H⋯O/O⋯H and H⋯C/C⋯H contacts are the most significant, at 48.7% and 29.8%, respectively.

Crystal structure and Hirshfeld surface analysis of (2²RS,2³SR,2⁵RS,2⁶SR)-2³,2⁵,5-tri­methyl-2¹-(2,2,2-tri­fluoro­acet­yl)-5-aza-2(2,6)-piperidina-1,3(2,5)-di­furana­cyclo­hexa­phan-2⁴-one

The title compound features a main twelve-membered difuryl ring with which the furan rings make dihedral angles of 76.14 (5) and 33.81 (5)°. In the crystal, C–H⋯O, C—H⋯F, C—H⋯π and C—F⋯π inter­actions link the mol­ecules into the chains along the b-axis direction, forming sheets parallel to the (001) plane. These sheets are also connected by van der Waals inter­action.

Crystal structure, Hirshfeld surface analysis and DFT study of (5E,5′E,6Z,6′Z)-6,6′-[ethane-1,2-diyl­bis­(aza­nylyl­idene)]bis­{5-[2-(4-fluoro­phen­yl)hydra­zono]-3,3-di­methyl­cyclo­hexa­none} 2.5-hydrate

The title compound was obtained by the condensation of ethyl­enedi­amine and (5E,5E,6Z,6Z)-6,6-[ethane-1,2-diylbis(aza­nylyl­idene)]bis­{5-[2-(4-fluoro­phen­yl)hydrazono)-3,3-di­methyl­cyclo­hexa­none} in ethanol and crystallized as a 1:2.5 hydrate containing two different conformers stabilized by intra­molecular N—H⋯N and linked by O—H⋯O (involving the water mol­ecules) hydrogen bonds.

Syntheses, crystal structures and thermal properties of catena-poly[cadmium(II)-di-μ-bromido-μ-pyridazine-κ²N¹:N²] and catena-poly[cadmium(II)-di-μ-iodido-μ-pyridazine-κ²N¹:N²]

In the crystal structures of the title compounds, the cadmium cations are octa­hedrally coordinated by four halide anions and two pyridazine ligands in a trans-CdX₄N₂ (X = Br, I) arrangement and are linked into chains by the halide anions and the pyridazine ligands.

Two polymorphs of N,N′-di­phenyl-2-[1-(propyl­amino)­ethyl­idene]propanedi­amide

Two polymorphs of the title compound, C₂₀H₂₃N₃O₂, have been isolated. Polymorph (I) crystallizes in the monoclinic space group P2₁/n and polymorph (II) in the tetra­gonal space group I4₁/a. The main difference between the two polymorphs on the mol­ecular level is the orientation of the n-propyl group. This group is anti­periplanar in (I) and synclinal in (II).

Syntheses, crystal structures and Hirshfeld surface analyses of N-aryl­sulfonyl derivatives of cytisine

Aryl­sulfonation of cytisine with three types of substituted aryl­sulfonyl chlorides produced products (I)–(III), the mol­ecular structures of which differ in the location of the benzene fragment relative to the cytisine core. Inter­molecular C—H⋯O hydrogen bonds cross-link the mol­ecules into infinite chains.

Co-crystal of nadifloxacin with oxalic acid

The nadifloxacin oxalic acid co-crystal is stabilized by inter­molecular hydrogen bonds. FT–IR, DSC and XRD studies were carried out to confirm the structure and a Hirshfeld surface analysis was performed to investigate the inter­molecular inter­actions.

Crystal structure of trimeth­yl({tris­[(phenyl­sulfan­yl)meth­yl]sil­yl}meth­oxy)silane and Hirshfeld surface analysis of 3-bromo-2,2-bis­(bromo­meth­yl)propan-1-ol

Trimeth­yl({tris­[(phenyl­sulfan­yl)meth­yl]sil­yl}meth­oxy)silane (3) is a new ligand for transition-metal coordination chemistry derived from 3-bromo-2,2-bis­(bromo­meth­yl)propan-1-ol (1) through silylation and following exchange of bromine groups with NaSPh. Analysis of the Hirshfeld surface shows structure-defining inter­actions for bromo­methyl­alcohol 1, resulting in inter­molecular hydrogen bonds between the hydroxyl groups along the a-axis direction.

Garnet-type Na₃Te₂(FeO₄)₃

The garnet-type crystal structure of Na₃Te₂(FeO₄)₃ shows high similarities with its isotypic analogues Na₃Te₂[(Fe_0.5Al_0.5)O₄]₃ and Na₃Te₂(GaO₄)₃.

Synthesis and crystal structure of N-(5-acetyl-4-methyl­pyrimidin-2-yl)benzene­sulfonamide

N-(5-Acetyl-4-methyl­pyrimidin-2-yl)benzene­sulfonamide was synthesized and structurally characterized. In the crystal, π–π inter­actions between the phenyl and pyrimidine groups of neighbouring mol­ecules form mol­ecular chains parallel to [010]. Adjacent chains are linked by N—H⋯N hydrogen-bonding inter­actions, resulting in a three-dimensional network.

Crystal structures of three homologues with increasing ring size: 2-meth­oxy-4-(thio­phen-2-yl)-5,6,7,8-tetra­hydro­quinoline-3-carbo­nitrile, 2-meth­oxy-4-(thio­phen-2-yl)-6,7,8,9-tetra­hydro-5H-cyclo­hepta­[b]pyridine-3-carbo­nitrile and 2-meth­oxy-4-(thio­phen-2-yl)-5,6,7,8,9,10-hexa­hydro­cyclo­octa[b]pyridine-3-carbo­nitrile

The title compounds form a homologous but non-isotypic series with appreciable differences in mol­ecular form. In each case, the packing is determined by two C—H⋯N hydrogen bonds.

Crystal structure of [tBuMgCl]₂[MgCl₂(Et₂O)₂]₂

The crystal structure of [tBuMgCl]₂[MgCl₂(Et₂O)₂]₂ features an Mg₄Cl₆ open-cube cluster with both four- and six-coordinate Mg²⁺ ions. The Cl⁻ ions adopt bridging positions. Inter­molecular C—H⋯Cl hydrogen bonds link adjacent units of the title compound into chains extending parallel to [010].

Crystal structure of tert-butyl 3,6-di­iodo­carbazole-9-carboxyl­ate

The crystal structure of tert-butyl 3,6-di­iodo­carbazole-9-carboxyl­ate features inter­molecular π–π inter­actions, as well as both type I and type II inter­molecular I⋯I inter­actions.

3,3′-(Phenyl­methyl­ene)bis­(1-ethyl-3,4-di­hydro-1H-2,1-benzo­thia­zine-2,2,4-trione): single-crystal X-ray diffraction study, quantum-chemical calculations and Hirshfeld surface analysis

The tautomeric form of 3,3′-(phenyl­methyl­ene)bis­(1-ethyl-3,4-di­hydro-1H-2,1-benzo­thia­zine-2,2,4-trione) with potential anti­microbial, analgesic, and anti-inflammatory activity was studied.

2,2′:4,4′′:4′,4′′′-Quaterpyridine: synthesis, crystal-structure description, and Hirshfeld surface analysis

The title compound, 2,2′:4,4′′:4′,4′′′-quaterpyridine (Qtpy), C₂₀H₁₄N₄, crystallizes in the triclinic P space group and has half of the mol­ecule in the asymmetric unit, corresponding to 4,4′-bi­pyridine (4,4′-bpy) that serves as the building block for the mol­ecule.

Crystal structure and Hirshfeld surface analysis of mono/bis­(aqua-κO)[N-(2-oxido­benzyl­idene)valinato-κ³O,N,O′]copper(II): dimeric Schiff base copper(II) complexes having different numbers of coordinated water mol­ecules

The mol­ecular structure of the title compound, [Cu(C₁₂H₁₃N₂O₃)(H₂O)₂]·[Cu(C₁₂H₁₃N₂O₃)(H₂O)], consists of two different mol­ecules in the asymmetric unit. Both of the structures consist of a tridentate ligand synthesized from L-valine and salicyl­aldehyde, and one water mol­ecule or two water mol­ecules coordinating to Cu^II.

Crystal structure and Hirshfeld surface analysis of N-{N-[amino­(di­methyl­amino)­meth­yl]carbamimido­yl}-3-bromo­benzene­sulfonamide

The crystal structure of the bromo­benzene­sulfonamide derivative of the type 2 diabetes drug metformin is presented.

Syntheses, crystal structures and Hirshfeld surface analysis of three salts of 1-(4-nitro­phenyl)­piperazine

Three salts of 4-nitro­phenyl­piperazine were synthesized and their crystal structures determined via X-ray diffraction.

Syntheses and crystal structures of four 4-(4-meth­oxy­phen­yl)piperazin-1-ium salts: tri­fluoro­acetate, 2,3,4,5,6-penta­fluoro­benzoate, 4-iodo­benzoate, and a polymorph with 4-methyl­benzoate

The syntheses and low-temperature (90 K) crystal structures of four organic salts of 4-(4-meth­oxy­phen­yl)piperazin-1-ium are presented.

Enanti­opure (S)-butan-2-yl N-(4-x-phen­yl)thio­carbamates, x = NO₂, OCH₃, F, and Cl

Enanti­opure (S)-butan-2-yl-N-(4-x-phen­yl)thio­carbamates, x = NO₂, OCH₃, F, and Cl were synthesized from reacting aryl iso­thio­cyanate with (S)-2-butanol to form new chiral crystals as the basis for future research into their non-linear physical and potentially biological properties.

Crystal structures of (12E)-12-(4-benzyl­idene)-7,7,16-tri­methyl-3-(4-methyl­phen­yl)-1-oxa-16-aza­tetra­cyclo­[11.2.1.0^2,11.0^4,9]hexa­deca-2(11),4(9)-dien-5-one and (12E)-12-(4-bromo­benzyl­idene)-73-(4-bromo­phen­yl)-,7,16-tri­methyl-10-oxa-16-aza­tetra­cyclo­[11.2.1.0^2,11.0^4,9]hexa­deca-2(11),4(9)-dien-5-one

The title compounds, C₃₂H₃₅NO₂, (I), and C₃₀H₂₉Br₂NO₂, (II), differ by the presence of a bromine atom instead of a methyl atom in the para position of two phenyl rings of compound (II), with an r.m.s. deviation of 0.27 Å between these compounds.

Synthesis, crystal structure and Hirshfeld surface analysis of the hybrid salt bis­(2-methyl­imidazo[1,5-a]pyridin-2-ium) tetra­chlorido­manganate(II)

The 0-D hybrid salt (C₈H₉N₂)₂[MnCl₄] with a pseudo-layered arrangement of the organic and inorganic sheets is isomorphous with the Zn and Cd analogues. According to the Hirshfeld surface analysis, non-conventional C—H⋯Cl—Mn hydrogen bonding is predominant in the crystal packing.

Crystal structure of bis­[octa­kis­(di­methyl sulfoxide-κO)­ytterbium(III)] penta­bromido­plumbate(II) tribromide di­methyl sulfoxide monosolvate: a ytterbium-doped lead halide perovskite precursor

A mixture of PbBr₂ and YbBr₃·nH₂O in a dimethyl sulfoxide (DMSO) solution yielded single crystals of a lead halide perovskite precursor with ytterbium, bis­[octa­kis­(di­methyl sulfoxide)­ytterbium(III)]penta­bromido­plumbate(II) tribromide with di­methyl sulfoxide as co-crystallite. These single crystals react with a caesium chloride solution, exhibiting near-infrared (NIR) luminescence by visible photoexcitation, suggesting the formation of Yb³⁺-doped lead halide perovskites

Two new cases of polymorphism in diagonally substituted rubrene derivatives

Two new cases of polymorphism in two different substituted rubrenes are reported. These are some of the first examples in rubrene derivatives of polymorphism occurring in a separate crystal class.