Journal of Chemical Crystallography最新文献

A new lead tri-magnesium phosphate PbMg₃(HPO₄)(PO₄)₂ was synthesized by hydrothermal method and characterized by single crystal X-ray diffraction. This phosphate crystallizes in the monoclinic system with space group I2/m and unit cell parameters a = 6.6403(2)Å, b = 13.1169(5) Å, c = 10.7153(4) Å and β = 90.194 (1)°. The structure consists of two edge-sharing [MgO₆] octahedra linked to [PO₄] or [HPO₄] tetrahedra to build [Mg₂P₂O₁₄] and [Mg₂H₂P₂O₁₄] moieties, which are interconnected together through vertices to form a sheet parallel to (1 0 0) plan. In addition, an infinite chain ([MgPO₉]_∞) formed by the sharing of a vertex between the [MgO₆] octahedron and the [PO₄] tetrahedron ensures the connection of the sheets to form a three-dimensional structure containing tunnels parallel to the b and c axes. The Pb²⁺ and H⁺ cations are located in disordered sites in these tunnels. The structure of this phosphate exhibits also a strong hydrogen bond.

Graphical Abstract

(A) and (C) Polyhedral representation of the structure showing the tunnels along the [010] and [001] directions that house Pb and H atoms. The dashed lines in the tunnels of (C) represent the hydrogen bond O1–H1…O1ⁱ. (B) Infinite chain [MgPO₉]_∞ formed by alternating [MgO₆] octahedra and [PO₄] tetrahedra, which connect the layers stacked along the c-axis.

The monomeric magnesium complex, C₄H₈N₅⁺[Mg(C₇H₂N₂O₇)₂(H₂O)₂]·2 H₂O, crystallizes in a triclinic P-1 space group. In this structure, Mg(II) ion adopts an octahedral geometry. The coordination sphere around the metal center is formed by four oxygen atoms from two bidentate 3,5-dinitrosalicylate anions (DNS) in the equatorial plane, while two oxygen atoms from coordinated water molecules occupy the axial positions. Extensive hydrogen bonding stabilizes the crystal structure with the non-coordinated 2,4,6-triaminopyrimidinium cation (TAP) generating primary ring motifs such as R₂²(8) and R₂³(8), which extend into a complex three-dimensional hydrogen-bonded network. Coordinated and non-coordinated water molecules play a crucial role in maintaining the supramolecular framework by engaging in N–H…O, O–H…O and O–H…N hydrogen bonding interactions. Additionally, π–π stacking interactions contribute to the stabilization of the structure. These cooperative non-covalent interactions not only strengthen the crystal packing but also contribute to the overall stability of the supramolecular architecture, making this complex a potential candidate for future studies in crystal engineering and molecular assembly.

A novel transition metal complex was synthesized from the reaction between the copper(II)acetate and the Schiff base ligand (E)-2,4-di-tert-butyl-6-((2-fluorophenylimino)methyl)phenol. The title complex was structurally characterized by single crystal X-ray diffraction technique. Crystallographic analysis revealed that the copper(II) center in the investigated complex is four-coordinate, consisting of two imine nitrogen atoms and two phenolic oxygen atoms from two bidentate Schiff bases. The coordination geometry is a distorted seesaw configuration with a τ4 index of 0.33. Hirshfeld surface analysis was employed to investigate the intermolecular contacts within the crystal structure using 3D d_norm surface and 2D fingerprint histograms. The fingerprint plots indicated that the dominant contacts were Van der Waals interactions (H···H, 74.3%), with C···H and H···F interactions also contributing significantly to the overall packing. Density functional theory calculations with the B3LYP/LanL2DZ level were used to calculate the molecular geometric structure of the Cu(II) complex in the ground state. The calculated values were compared with the crystallographic one. Additionally, Natural Bond Orbital (NBO) analysis was performed using the same basis set. The electronic properties of the atoms within the coordination environment and their hyperconjugative interactions were evaluated using NBO analysis.

Graphical Abstract

In this study, the synthesis of a copper(II) complex compound, some DFT calculations, single-crystal X-ray and Hirshfeld surface analyses were performed and interpreted

The compound 1,4,7-trithia-10,13-diazacyclopentadecane-9,14-dione, 1, crystallizes in the space group P2₁/c with a = 9.3608(3) Å, b = 16.0333(5) Å, c = 9.5608(3) Å, β = 113.3521(14)°, and Z = 4. The title molecule forms chains via face-to-face N–H^…O hydrogen bonds. The structure of 1 is also compared to the previously reported oxygen analog, 1,4,7-trioxa-10,13-diazacyclopentadecane-9,14-dione.

Reaction of even parity primary alkyl amines with propanesultone produces 3-(N-alkylammonium)propanesulfonate inner salts as slightly-soluble solids in polar solvents and in good yields. A short series of amines, n-C_nH_2n+1NH₂ with n = 4, 6, 8, 10, was studied. Crystals of the N-butyl analog from water occurred as a dihydrate, orthorhombic, P nma, with molecules lying on mirror planes and waters in general positions. Secondary ammonium ions are hydrogen-bonded to waters of crystallization, which are hydrogen-bonded to sulfonate oxygens with only two-centered⁺N-H…O_w and O-H…O^- interactions. Beginning with the N-hexyl homolog, crystals are polycrystalline, fibrous and with sufficient alignment coherence to allow determination as though single crystals. The degree of fiber misalignment was 3–5^o, approximately. Crystals from water are triclinic (unsolvated), P -1, with molecules lying between crystal (0 2 2) planes. Molecular packing shows adjacent molecules hydrogen-bonded between secondary ammonium ions and sulfonate ions in which all ⁺N-H…(O, O’)^- interactions are three-centered. Terminal alkyl groups pack in adjacent regions so that both hydrogen-bonding and dispersion attractions contribute to increasing intermolecular attractions and melting temperatures, exceeding 260 ^oC for the N-decyl homolog. The four compounds are further characterized by infrared spectroscopy and proton and carbon magnetic resonance spectroscopy and solubilities in common solvents.

Graphical Abstract

3-(N-Butylammonium)propanesulfonate zwitterions are mirror symmetric in P nma, while hexyl, octyl and decyl homologs are fibrous triclinic (P -1) structures with molecules lying approximately along the (0 1 1) planes

Methyl 2,3-di-O-benzyl-α-d-(4-²H)-glucopyranoside, C₂₁H₂₅DO₆, is an intermediate used in synthesis of oligosaccharides. The hexopyranose ring has the ⁴C₁ chair conformation in the crystal structure. The exocyclic groups of the hexose sugar show for the glycosidic torsion angle ϕ =−52.8° and for the hydroxymethyl group the gauche-gauche conformation with ω = −64.7°, one of the two main orientations of the latter group in hexopyranose sugars that have the gluco-configuration, i.e., with an equatorial hydroxyl group at C4. The benzene rings of the benzyl groups are arranged with an angle of 56.9° to each other within the molecule and show intramolecular as well as intermolecular C-H···π interactions. A chain of intermolecular hydrogen bonds exists along the b-axis involving O4 and O6 atoms. The experimentally observed peak in the infrared spectrum at 2159 cm^− 1 was ascribed to the stretching of the C4–D4 bond based on DFT calculations.

Graphical Abstract

In the structure of the monosaccharide methyl 2,3-di-O-benzyl-α-d-(4-²H)-glucopyranoside, C₂₁H₂₅DO₆, the two hydroxyl groups HO4 and HO6 act as both donors and acceptors resulting in an intermolecular hydrogen bond chain along the b-axis direction.

ALZ-801 (valiltramiprosate) is an orally bioavailable, small-molecule inhibitor of β-amyloid (Aβ) oligomer formation in late-stage clinical development as a potential disease-modifying treatment for Alzheimer’s disease (AD). ALZ-801, (S)-3-(2-amino-3-methylbutanamido) propane-1-sulfonic acid, is a valine-conjugated prodrug of tramiprosate. Structural, polymorphic analysis of the active pharmaceutical ingredient (API) of ALZ-801 showed extra peaks when high throughput transmission mode XRPD analysis was utilized. After extensive investigation, the extra peaks were determined to be an artifact of transmission mode XRPD, which was not observed in either reflectance or capillary mode XRPD analyses. Reflectance mode XRPD was demonstrated as the most appropriate methodology to monitor the crystal form of ALZ-801 API. In conclusion, ALZ-801 API is a single, pure polymorph form.

Graphical Abstract

A single crystalline form of ALZ-801 is observed in a range of crystal morphologies, the risk of a change in solid form affecting the delivery of this potential new disease modifying therapy for Alzheimer’s disease is negligible

Phase light microscopy image of ALZ-801 crystal pattern 1 (single polymorph). ALZ-801 crystals occur in diverse ranges of morphologies, i.e., tetrahedron (a), bladed, needles, dodecahedron, slices(b), prismatic (c) and tabular (d) forms

In this work by means of the neutralization reaction of the N,N-dimethylbenzylamine, 3,5-dinitrobenzoic acid, 3,5-dinitrosalicylic acid and naphthalene-1,5-disulfonic acid, three bi- and tri-component crystalline salt systems are made by the gradual solvent volatilization method. The detailed features have been thoroughly conducted by the set of the analytical performances embracing the single crystal X-ray diffraction (SC-XRD), IR and EA, the melting points (m.p.s) were also measured. Their structural and supramolecular facets were analyzed in detail according to the noncovalent linkages and the supramolecular synthons. The role of the major intermolecular contacts was evaluated further by the Hirshfeld surface analysis (HSA) suite of programme for illucidating their importances. All the salts demonstrated the 3D net structures for the collective effect of the various non-covalent contacts. All contained the identical mol stoichiometry of 1:1 rate between the dmba & the number of the acidic units and embraced the N–H···O & O–H···O Hbonds together with the other non-covalent connections. Within all the salts, the respective residues are permanently tethered to each other via the energetic Hbonds belonging to the ionic N_{N,N-dimethylbenzylaminium}–O_acid fashion. Other extensive non-covalent connections of CH···O/CH₂···O/CH₃···O, C_π···π, CH···π/CH₃···π and π···π also function appreciable roles in the spatial expandings. The salts demonstrated the R₂²(4), R₂²(7), R₂²(12), R₂²(15), R₄³(11), R₄³(12), R₄⁴(20), R₄⁴(22), R₆⁵(30) and R₈⁸(44) rings. For the synergism of the traditional Hbonds and the diversified non-covalent connections, all applied the 3D appearances.

Graphical Abstract

The structures of the salts from dmba, 3,5-dinitrobenzoic acid, 3,5-dinitrosalicylic acid, and naphthalene-1,5-disulfonic acid are predominantly stabilized by the classical Hbonds together with the CH···O/CH₂···O/CH₃···O, C_π···π, CH···π/CH₃···π & π···π associates, erecting the 3D graphs.

Salt metathesis reaction between equimolar ratios of [Li{ArNC(NMe₂)Nar}(THF)] (Ar = C₆H₃Prⁱ₂-2,6) and CrCl₃ in tetrahydrofuran (THF) leads to a mono(guanidiante) chromium(III) chloride complex, [Cr{ArNC(NMe₂)Nar}Cl₂(THF)₂]. X-ray analysis confirms it to be monomeric in solid state in which guanidinate ligand is coordinated in bidentate fashion to the six coordinated Cr center. The octahedral coordination is completed by two chloride atoms and two THF molecules. The herein reported compound is the first example of monomeric chromium halides of guanidinate ligands. Hirshfeld surface analyses indicate that H∙∙∙H interactions, H∙∙∙C/C∙∙∙H and H∙∙∙Cl/Cl∙∙∙H H–bonds are the three and at times the strongest contributions for the intermolecular interactions. The title compound, [C₃₅H₅₆Cl₂CrN₃O₂], crystallized in the monoclinic space group, P2₁/n with cell parameters: a = 11.5340(7) b = 17.6830(11) c = 18.0320(11) Å, β = 92.410(5), V = 3674.5(4) A³, Z = 4.

Reaction of 1,4-bis(1H-imidazol-1-yl)benzene ligand (bib) and CuSiF₆ in water/ dimethylsulfoxide (DMSO) as the solvent mixture affords purple crystals of a metal-organic framework, 1, suitable for single crystal X-ray diffraction (SCXRD) analysis. 1 crystallizes in the triclinic P − 1 space group: a = 12.694(2) Å, b = 13.455(2) Å, c = 13.740(3) Å, α = 88.919(7)°, β = 67.864(7)°, γ = 65.029(6)°, V = 1942.9(6) ų. 1 was found to be a new phase of SIFSIX-23-Cu. Moreover, in the structure pores a cluster formed by two molecules of DMSO and ten molecules of water was identified possessing a double ice Ih-like shape.