Crystal structure and Hirshfeld surface analysis of 1-[6-bromo-2-(4-fluoro-phen-yl)-1,2,3,4-tetra-hydroquinolin-4-yl]pyrrolidin-2-one

In the title compound, C19H18BrFN2O, the pyrrolidine ring adopts an envelope conformation. In the crystal, mol-ecules are linked by inter-molecular N-H⋯O, C-H⋯O, C-H⋯F and C-H⋯Br hydrogen bonds, forming a three-dimensional network. In addition, C-H⋯π inter-actions connect mol-ecules into ribbons along the b-axis direction, consolidating the mol-ecular packing. The inter-molecular inter-actions in the crystal structure were qu-anti-fied and analysed using Hirshfeld surface analysis.

Crystal structure and Hirshfeld surface analysis of 3,3'-[ethane-1,2-diylbis(-oxy)]bis-(5,5-di-methyl-cyclo-hex-2-en-1-one) including an unknown solvate

The title mol-ecule, C18H26O4, consists of two symmetrical halves related by the inversion centre at the mid-point of the central -C-C- bond. The hexene ring adopts an envelope conformation. In the crystal, the mol-ecules are connected into dimers by C-H⋯O hydrogen bonds with R 2 2(8) ring motifs, forming zigzag ribbons along the b-axis direction. According to a Hirshfeld surface analysis, H⋯H (68.2%) and O⋯H/H⋯O (25.9%) inter-actions are the most significant contributors to the crystal packing. The contribution of some disordered solvent to the scattering was removed using the SQUEEZE routine [Spek (2015 ▸). Acta Cryst. C71, 9-18] in PLATON. The solvent contribution was not included in the reported mol-ecular weight and density.

Crystal structure and Hirshfeld surface analysis of 8-benzyl-1-[(4-methyl-phen-yl)sulfon-yl]-2,7,8,9-tetra-hydro-1H-3,6:10,13-diep-oxy-1,8-benzodi-aza-cyclo-penta-decine ethanol hemisolvate

The asymmetric unit of the title compound, 2C31H28N2O4S·C2H6O, contains a parent mol-ecule and a half mol-ecule of ethanol solvent. The main compound stabilizes its mol-ecular conformation by forming a ring with an R 1 2(7) motif with the ethanol solvent mol-ecule. In the crystal, mol-ecules are connected by C-H⋯O and O-H⋯O hydrogen bonds, forming a three-dimensional network. In addition, C-H⋯π inter-actions also strengthen the mol-ecular packing.

Crystal structure and Hirshfeld surface analysis of dimethyl 4-hy-droxy-5,4'-dimethyl-2'-(toluene-4-sulfonyl-amino)-biphenyl-2,3-di-carboxyl-ate

In the title compound, C25H25NO7S, the mol-ecular conformation is stabilized by intra-molecular O-H⋯O and N-H⋯O hydrogen bonds, which form S(6) and S(8) ring motifs, respectively. The mol-ecules are bent at the S atom with a C-SO2-NH-C torsion angle of -70.86 (11)°. In the crystal, mol-ecules are linked by C-H⋯O and N-H⋯O hydrogen bonds, forming mol-ecular layers parallel to the (100) plane. C-H⋯π inter-actions are observed between these layers.

Crystal structure and Hirshfeld surface analysis of 10-hy-droxy-2-(4-meth-oxy-phen-yl)-3-oxo-2,3,3a,4,10,10a-hexa-hydro-1H-9-thia-2-aza-cyclo-penta-[b]fluorene-4-carb-oxy-lic acid dimethyl sulfoxide-d6 monosolvate

In the title compound, C22H19NO5S·C2D6OS, the central six-membered ring has a slightly distorted boat conformation, while the fused pyrrolidine ring adopts an envelope conformation. These conformations are stabilized by O-H⋯O hydrogen bonds between the main compound and solvent mol-ecules. In addition, intra-molecular C-H⋯O hydrogen bonds in the main mol-ecule form two S(6) rings. Mol-ecules are connected by pairs of inter-molecular C-H⋯O hydrogen bonds, forming dimers with a R 2 2(8) motif. These dimers form a three-dimensional network through O-H⋯O, O-H⋯S and C-H⋯O hydrogen bonds with each other directly and through solvent mol-ecules. In addition, weak π-π stacking inter-actions [centroid-to-centroid distances = 3.9937 (10) and 3.9936 (10) Å, slippages of 2.034 and 1.681 Å] are observed. The inter-molecular contacts were qu-anti-fied using Hirshfeld surface analysis and two-dimensional fingerprint plots, revealing the relative contributions of the contacts to the crystal packing to be H⋯H 41.7%, O⋯H/H⋯O 27.7%, C⋯H/H⋯C 17.0%, and S⋯H/H⋯S 7.5%.

Quasi-aromatic Möbius chelates of Cadmium(II) nitrite and/or nitrate

We report the design, structural, spectroscopic and computational characterizations of the two new quasi-aromatic Möbius chelate coordination compounds fabricated from Cd(NO3)2·4H2O and a bulky helical organic ligand derived from benzildihydrazone...

Solvent-driven structural topologies in phenanthroline-based co-crystals of Zn(ii) involving fascinating infinite chair-like {[(bzH)4Cl2]2−}n assemblies and unconventional layered infinite {bz-H2O-Cl}n anion-water clusters: antiproliferative evaluation and theoretical studies

Anticancer activities considering cell cytotoxicity, apoptosis and molecular docking have been explored in Zn(ii) co-crystals of phenanthroline involving infinite chair-like assemblies and unconventional layered infinite anion-water clusters.

Evaluation of the antitumor activity of a series of the pincer-type metallocomplexes produced from isonicotinohydrazide derivative

In this work we report on the antitumor properties of a series of pincer-type metallocomplexes [Hg₂(HL-keto)Cl₄]_n (1), [Hg(HL-keto)I₂] (2) and [Mn(HL-zwitterion)Cl₂]∙MeOH (3∙MeOH), derived from N'-(1-(pyridin-2-yl)ethylidene)isonicotinohydrazide (HL) and corresponding metal salts. The Hg(II) and Mn(II) salts are chelated by the keto (HL-keto) or zwitterionic (HL-zwitterion) form of HL, respectively. The cytotoxic effects of these compounds have been accessed against lung adenocarcinoma (A549) and hepatocellular carcinoma (HepG2 and Huh7) cell lines. Complexes 1 and 2 were found to be most efficient against the cell line Huh7 with IC₅₀ value of 2.56 and 9.90 μM, respectively, while they exhibit moderate activity towards cell lines A549 and HepG2, as evidenced from IC₅₀ values in the range 27.98-56.99 μM. Complex 3∙MeOH is less efficient towards all the three cell lines with relatively high IC₅₀ values. The mechanisms of the metallocomplexes killing the aforementioned cells were elucidated by flow cytometry, colony formation and polymerase chain reaction (PCR) analysis of apoptosis related expression of the genes. The results of the cytotoxic effects and antitumor activity on different cell lines are affected by the metal nature and the presence of the coordinated halide.

Crystal structure and Hirshfeld surface analysis of (E)-3-[(4-methyl-benzyl-idene)amino]-5-phenylthiazolidin-2-iminium bromide N,N-di-methyl-formamide monosolvate

In the cation of the title salt, C17H18N3S+·Br-·C3H7NO, the central thia-zolidine ring adopts an envelope conformation with puckering parameters Q(2) = 0.310 (3) Å and φ(2) = 42.2 (6)°. In the crystal, each cation is connected to two anions by N-H⋯ Br hydrogen bonds, forming an R 4 2(8) motif parallel to the (10) plane. van der Waals inter-actions between the cations, anions and N,N-di-methyl-formamide mol-ecules further stabilize the crystal structure in three dimensions. The most important contributions to the surface contacts are from H⋯H (55.6%), C⋯H/H⋯C (17.9%) and Br⋯H/H⋯Br (7.0%) inter-actions, as concluded from a Hirshfeld analysis.

(E)-1-(2,6-Di-chloro-phen-yl)-2-(3-nitro-benzyl-idene)hydrazine: crystal structure and Hirshfeld surface analysis

The stabilized conformation of the title compound, C13H9Cl2N3O2, is similar to that of the isomeric compound (E)-1-(2,6-di-chloro-phen-yl)-2-(2-nitro-benzyl-idene)hydrazine. The 2,6-di-chloro-phenyl ring and the nitro-substituted benzene ring form a dihedral angle of 26.25 (16)°. In the crystal, face-to-face π-π stacking inter-actions along the a-axis direction occur between the centroids of the 2,6-di-chloro-phenyl ring and the nitro-substituted benzene ring. The mol-ecules are further linked by C-H⋯O contacts and N-H⋯O and C-H⋯Cl hydrogen bonds, forming pairs of hydrogen-bonded mol-ecular layers parallel to (100). The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions to the crystal packing are from H⋯H (22.1%), Cl⋯H/H⋯Cl (20.5%), O⋯H/H⋯O (19.7%), C⋯C (11.1%) and C⋯H/H⋯C (8.3%) inter-actions.

Crystal structure and Hirshfeld surface analysis of phen-yl(5,7,8a-triphenyl-1,2,3,7,8,8a-hexa-hydro-imidazo[1,2-a]pyridin-6-yl)methanone with an unknown solvent

In the title compound, C32H28N2O, the imidazolidine and pyridine rings of the central hexa-hydro-imidazo[1,2-a]pyridine ring system adopt envelope and screw-boat conformations, respectively. The mol-ecule exhibits two weak intra-molecular π-π inter-actions between phenyl rings. In the crystal, mol-ecules are linked via pairs of C-H⋯ O hydrogen bonds, forming inversion dimers. The dimers are further linked by pairs of C-H⋯π inter-actions, forming infinite chains along the c-axis direction. A Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (73.4%), C⋯H/H⋯C (18.8%) and O⋯H/H⋯O (5.7%) contacts. The contribution of some disordered solvent to the scattering was removed using the SQUEEZE routine [Spek (2015 ▸). Acta Cryst. C71, 9-18] in PLATON. The solvent contribution was not included in the reported mol-ecular weight and density.

Crystal structure and Hirshfeld surface analysis of (E)-1-(2,6-di-chloro-phen-yl)-2-(2-nitro-benzyl-idene)hydrazine

In the title compound, C13H9Cl2N3O2, the 2,6-di-chloro-phenyl ring and the nitro-substituted benzene ring form a dihedral angle of 21.16 (14)°. In the crystal, face-to-face π-π stacking inter-actions occur along the a-axis direction between the centroids of the 2,6-di-chloro-phenyl ring and the nitro-substituted benzene ring. Furthermore, these mol-ecules show intra-molecular N-H⋯Cl and C-H⋯O contacts and are linked by inter-molecular N-H⋯O and C-H⋯Cl hydrogen bonds, forming pairs of hydrogen-bonded mol-ecular layers parallel to (20). The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions to the crystal packing are from H⋯H (23.0%), O⋯H/H⋯O (20.1%), Cl⋯H/H⋯Cl (19.0%), C⋯C (11.2%) and H⋯C/C⋯H (8.0%) inter-actions.

Crystal structure and Hirshfeld surface analysis of (E)-4-{2,2-di-chloro-1-[(3,5-di-methyl-phen-yl)diazen-yl]ethen-yl}-N,N-di-methyl-aniline

In the title compound, C18H19Cl2N3, the planes of the benzene rings subtend a dihedral angle of 77.07 (10)°. In the crystal, mol-ecules are associated into inversion dimers via short Cl⋯Cl contacts [3.3763 (9) Å]. A Hirshfeld surface analysis indicates that the most important contact percentages for the different types of inter-actions are H⋯H (43.9%), Cl⋯H/H⋯Cl (22.9%), C⋯H/H⋯C (20.8%) and N⋯H/H⋯N (8.0%).

Novel Pb(II) Complexes: X-Ray Structures, Hirshfeld Surface Analysis and DFT Calculations

Herein we report the synthesis and detailed structural characterization of two new centrosymmetric dinuclear coordination compounds of Pb(II) [Pb2L2(NCS)4] (1) and [Pb2L2(NO3)4]∙2MeOH (2), using the organic ligand 1,2-diphenyl-1,2-bis((methyl(pyridin-2-yl)methylene)hydrazono)ethane (L). In both complexes, each subunit [PbLX2 (X = NO3 or NCS)] adopts a quasi-aromatic Möbius metal chelate structure. Each ligand L is coordinated in a tetradentate coordination mode to Pb(II), yielding the 12π electron chelate ring via two pyridyl-imine units. In compound (1), the coordination sphere is completed by one disordered N,S-coordinated thiocyanate anion and two μ1,1-bridging N-coordinated thiocyanate anions. In compound (2), the coordination sphere of Pb(II) is completed by two monodentate and two bidentate nitrato ligands (two of them acting as bridging ligands). Crystal packing of both compounds is stabilized by intermolecular hydrogen bonds, intra- and intermolecular C–H∙∙∙π interactions. The Hirshfeld molecular surfaces of (1) and (2) demonstrate that their packing is dominated by C–H∙∙∙O/N/S interactions as well as by far less favored H∙∙∙H contacts.

Crystal structure and Hirshfeld surface analysis of 4-{2,2-di-chloro-1-[(E)-(4-chloro-phen-yl)diazen-yl]ethen-yl}-N,N-di-methyl-aniline

The title compound, C16H14Cl3N3, comprises three mol-ecules of similar shape in the asymmetric unit. The crystal cohesion is ensured by inter-molecular C-H⋯N and C-H⋯Cl hydrogen bonds in addition to C-Cl⋯π inter-actions. Hirshfeld surface analysis and two-dimensional fingerprint plots reveal that Cl⋯H/H⋯Cl (33.6%), H⋯H (27.9%) and C⋯H/H⋯C (17.6%) are the most important contributors towards the crystal packing.

Crystal structure and Hirshfeld surface analysis of 4-{2,2-di-chloro-1-[(E)-(4-fluoro-phen-yl)diazen-yl]ethen-yl}-N,N-di-methyl-aniline

In the title compound, C16H14Cl2FN3, the dihedral angle between the two aromatic rings is 64.12 (14)°. The crystal structure is stabilized by a short Cl⋯H contact, C-Cl⋯π and van der Waals inter-actions. The Hirshfeld surface analysis and two-dimensional fingerprint plots show that H⋯H (33.3%), Cl⋯H/H⋯Cl (22.9%) and C⋯H/H⋯C (15.5%) inter-actions are the most important contributors towards the crystal packing.

Complexes of BiCl3 with hydrazone derived ligands: a Möbius-like discrete metal chelate versus a salt-like porous polymeric structure

Reaction of BiCl₃ with hydrazone derived ligands yielded a new Möbius-like discrete metal chelate [Bi(LI)Cl3] and a salt-like porous polymeric structure ([H2LII]2[BiCl5]·EtOH)n.

Antitumor effects of novel nickel–hydrazone complexes in lung cancer cells

Two novel nickel(ii) complexes [NiL^I]·CH₃CN (1·CH₃CN) and [Ni(H₂L^II)(NCS)₂]·0.5H₂O (2·0.5H₂O) were fabricated and in in vitro experiments they both showed the dose dependent cytotoxicity and killed A549 lung cancer cells via an apoptotic pathway.

Crystal structures and Hirshfeld surface analyses of the two isotypic compounds (E)-1-(4-bromo-phen-yl)-2-[2,2-di-chloro-1-(4-nitro-phen-yl)ethen-yl]diazene and (E)-1-(4-chloro-phen-yl)-2-[2,2-di-chloro-1-(4-nitro-phen-yl)ethen-yl]diazene

In the two isotypic title compounds, C14H8BrCl2N3O2, (I), and C14H8Cl3N3O2, (II), the substitution of one of the phenyl rings is different [Br for (I) and Cl for (II)]. Aromatic rings form dihedral angles of 60.9 (2) and 64.1 (2)°, respectively. Mol-ecules are linked through weak X⋯Cl contacts [X = Br for (I) and Cl for (II)], C-H⋯Cl and C-Cl⋯π inter-actions into sheets parallel to the ab plane. Additional van der Waals inter-actions consolidate the three-dimensional packing. Hirshfeld surface analysis of the crystal structures indicates that the most important contributions for the crystal packing for (I) are from C⋯H/H⋯C (16.1%), O⋯H/H⋯O (13.1%), Cl⋯H/H⋯Cl (12.7%), H⋯H (11.4%), Br⋯H/H⋯Br (8.9%), N⋯H/H⋯N (6.9%) and Cl⋯C/C⋯Cl (6.6%) inter-actions, and for (II), from Cl⋯H / H⋯Cl (21.9%), C⋯H/H⋯C (15.3%), O⋯H/H⋯O (13.4%), H⋯H (11.5%), Cl⋯C/C⋯Cl (8.3%), N⋯H/H⋯N (7.0%) and Cl⋯Cl (5.9%) inter-actions. The crystal of (I) studied was refined as an inversion twin, the ratio of components being 0.9917 (12):0.0083 (12).

Crystal structure and Hirshfeld surface analysis of (E)-4-{[2,2-di-chloro-1-(4-meth-oxy-phen-yl)ethen-yl]diazen-yl}benzo-nitrile

In the title compound, C16H11Cl2N3O, the 4-meth-oxy-substituted benzene ring makes a dihedral angle of 41.86 (9)° with the benzene ring of the benzo-nitrile group. In the crystal, mol-ecules are linked into layers parallel to (020) by C-H⋯O contacts and face-to-face π-π stacking inter-actions [centroid-centroid distances = 3.9116 (14) and 3.9118 (14) Å] between symmetry-related aromatic rings along the a-axis direction. A Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from Cl⋯H/H⋯Cl (22.8%), H⋯H (21.4%), N⋯H/H⋯N (16.1%), C⋯H/H⋯C (14.7%) and C⋯C (9.1%) inter-actions.

Crystal structure and Hirshfeld surface analysis of (E)-3-[(4-chloro-benzyl-idene)amino]-5-phenyl-thia-zolidin-2-iminium bromide

The title salt, C16H15ClN3S+·Br-, is isotypic with (E)-3-[(4-fluoro-benzyl-idene)amino]-5-phenyl-thia-zolidin-2-iminium bromide [Khalilov et al. (2019 ▸). Acta Cryst. E75, 662-666]. In the cation of the title salt, the atoms of the phenyl ring attached to the central thia-zolidine ring and the atom joining the thia-zolidine ring to the benzene ring are disordered over two sets of sites with occupancies of 0.570 (3) and 0.430 (3). The major and minor components of the disordered thia-zolidine ring adopt slightly distorted envelope conformations, with the C atom bearing the phenyl ring as the flap atom. In the crystal, centrosymmetrically related cations and anions are linked into dimeric units via N-H⋯Br hydrogen bonds, which are further connected by weak C-H⋯Br contacts into chains parallel to the a axis. Furthermore, not existing in the earlier report of (E)-3-[(4-fluoro-benzyl-idene)amino]-5-phenyl-thia-zolidin-2-iminium bromide, C-H⋯π inter-actions and π-π stacking inter-actions [centroid-to-centroid distance = 3.897 (2) Å] between the major components of the disordered phenyl ring contribute to the stabilization of the mol-ecular packing. Hirshfeld surface analysis and two-dimensional fingerprint plots indicate that the most important contributions for the crystal packing are from H⋯H (30.5%), Br⋯H/H⋯Br (21.2%), C⋯H/H⋯C (19.2%), Cl⋯H/H⋯Cl (13.0%) and S⋯H/H⋯S (5.0%) inter-actions.

Crystal structure and Hirshfeld surface analysis of (E)-3-[(4-fluoro-benzyl-idene)amino]-5-phenyl-thia-zolidin-2-iminium bromide

In the cation of the title salt, C16H15FN3S+·Br-, the phenyl ring is disordered over two sets of sites with a refined occupancy ratio of 0.503 (4):0.497 (4). The mean plane of the thia-zolidine ring makes dihedral angles of 13.51 (14), 48.6 (3) and 76.5 (3)° with the fluoro-phenyl ring and the major- and minor-disorder components of the phenyl ring, respectively. The central thia-zolidine ring adopts an envelope conformation. In the crystal, centrosymmetrically related cations and anions are linked into dimeric units via N-H⋯Br hydrogen bonds, which are further connected by weak C-H⋯Br hydrogen bonds into chains parallel to [110]. Hirshfeld surface analysis and two-dimensional fingerprint plots indicate that the most important contributions to the crystal packing are from H⋯H (44.3%), Br⋯H/H⋯Br (16.8%), C⋯H/H⋯C (13.9%), F⋯H/H⋯F (10.3%) and S⋯H/H⋯S (3.8%) inter-actions.

Crystal structure and Hirshfeld surface analysis of (E)-1-[2,2-di-chloro-1-(4-nitro-phen-yl)ethen-yl]-2-(4-fluoro-phen-yl)diazene

In the title compound, C14H8Cl2FN3O2, the 4-fluoro-phenyl ring and the nitro-substituted benzene ring form a dihedral angle of 63.29 (8)°. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds into chains running parallel to the c axis. The crystal packing is further stabilized by C-Cl⋯π, C-F⋯π and N-O⋯π inter-actions. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions to the crystal packing are from H⋯O/O⋯H (15.5%), H⋯H (15.3%), Cl⋯H/H⋯Cl (13.8%), C⋯H/H⋯C (9.5%) and F⋯H/H⋯F (8.2%) inter-actions.

Arylhydrazone ligands as Cu-protectors and -catalysis promoters in the azide-alkyne cycloaddition reaction

A series of water soluble copper(ii) complexes, [Cu(κO¹O²N-H₂L¹)(H₂O)₂]·2H₂O (2), [Cu(κO-H₃L¹)₂(H₂O)₄] (3), [Cu(κO-H₄L²)₂(H₂O)₄] (5) and [Cu(H₂O)₆]·2H₂L³·2(CH₃)₂NCHO (7), were prepared by the reaction of Cu(NO₃)₂·3H₂O with sodium (Z)-2-(2-(1-amino-1,3-dioxobutan-2-ylidene)hydrazineyl)benzenesulfonate, [Na(μ₄-1:2κO¹,2κO²,3κO³,4κO⁴-H₃L¹)]_n (1; for 2 and 3), sodium (Z)-3-(2-(1-amino-1,3-dioxobutan-2-ylidene)hydrazineyl)-4-hydroxybenzene-sulfonate, [Na(μ-1κO¹,2κO²-H₄L²)]₂ (4; for 5) or sodium (Z)-2-(2-(1,3-dioxo-1-(phenylamino)butan-2-ylidene)hydrazineyl)naphthalene-1-sulfonate, [Na(μ-1κO¹O²,2κO³-H₂L³)(CH₃OH)₂]₂ (6; for 7). Compounds 1-7 were fully characterized, also by single-crystal X-ray diffraction analysis, and applied as homogeneous catalysts for the azide-alkyne cycloaddition (AAC) reaction to afford 1,4-disubstituted 1,2,3-triazoles. A structure-catalytic activity relationship has been recognized for the first time on the basis of the occurrence of resonance- and charge-assisted hydrogen bond interactions (RAHB and CAHB), in charge and ligand binding modes, enabling the catalytic activity of the compounds to be ordered as follows: Cu(NO₃)₂≪7 (complex salt with RAHB and CAHB) < 3 (with RAHB and CAHB) < 5 (with RAHB) < 2 (neither RAHB nor CAHB). Complex 2, without such non-covalent interactions, was found to be the most efficient catalyst for the AAC reaction, affording up to 98% product yield after being placed for 15 min, at 125 °C, in a water/acetonitrile mixture under low power (10 W) MW irradiation.

The effect of the orientation of the Jahn–Teller distortion on the magnetic interactions of trinuclear mixed-valence Mn(ii)/Mn(iii) complexes

The effect of the orientation of the Jahn–Teller distortion on the magnetic interactions in two new mixed-valence trinuclear Mn(iii)–Mn(ii)–Mn(iii) complexes has been investigated.

Structural versatility of the quasi-aromatic Möbius type zinc(ii)-pseudohalide complexes – experimental and theoretical investigations

In this contribution we report for the first time fabrication, isolation, structural and theoretical characterization of the quasi-aromatic Möbius complexes [Zn(NCS)₂L^I] (1), [Zn₂(μ_1,1-N₃)₂(L^I)₂][ZnCl₃(MeOH)]₂·6MeOH (2) and [Zn(NCS)L^II]₂[Zn(NCS)₄]·MeOH (3), constructed from 1,2-diphenyl-1,2-bis((phenyl(pyridin-2-yl)methylene)hydrazono)ethane (L^I) or benzilbis(acetylpyridin-2-yl)methylidenehydrazone (L^II), respectively, and ZnCl₂ mixed with NH₄NCS or NaN₃. Structures 1–3 are dictated by both the bulkiness of the organic ligand and the nature of the inorganic counter ion. As evidenced from single crystal X-ray diffraction data species 1 has a neutral discrete heteroleptic mononuclear structure, whereas, complexes 2 and 3 exhibit a salt-like structure. Each structure contains a Zn^II atom chelated by one tetradentate twisted ligand L^I creating the unusual Möbius type topology. Theoretical investigations based on the EDDB method allowed us to determine that it constitutes the quasi-aromatic Möbius motif where a metal only induces the π-delocalization solely within the ligand part: 2.44|e| in 3, 3.14|e| in 2 and 3.44|e| in 1. It is found, that the degree of quasi-aromatic π-delocalization in the case of zinc species is significantly weaker (by ∼50%) than the corresponding estimations for cadmium systems – it is associated with the Zn–N bonds being more polar than the related Cd–N connections. The ETS-NOCV showed, that the monomers in 1 are bonded primarily through London dispersion forces, whereas long-range electrostatic stabilization is crucial in 2 and 3. A number of non-covalent interactions are additionally identified in the lattices of 1–3.

Interplay between various types of non-covalent interactions allowed for isolation of rare examples of Zn(ii) based quasi-aromatic Möbius type species.

Crystal structure of (Z)-2-(2-(1,3-dioxo-1-(phenylamino)butan-2-ylidene)hydrazineyl) terephthalic acid-dimethylsulfoxide (1/1), C18H15N3O6 ⋅ C2H6OS

C18H15N3O6 ⋅ C2H6OS, P21/c (no. 14), a = 15.762(9) Å, v = 6.013(4) Å, c = 22.264(11) Å, β = 103.522(19)°, V = 2052(2) Å3, Z = 4, Rgt(F) = 0.0484, wRref(F2) = 0.1348, T = 296(2) K.

Crystal structure of dimethyl (3aS,6R,6aS,7S)-1H,3H,6H,7H-3a,6:7,9a-diepoxybenzo[de]isochromene-3a 1,6a-dicarboxylate, C16H16O7

C16H16O7, monoclinic, P21/n (no. 14), a = 12.830(3) Å, b = 8.1101(16) Å, c = 14.900(3) Å, β = 114.88(3)°, V = 1406.5(6) Å3, Z = 4, R gt(F) = 0.0578, wR ref(F 2) = 0.1799, T = 100(2) K.

Synthesis of Metallomacrocycle and Coordination Polymers with Pyridine-Based Amidocarboxylate Ligands and Their Catalytic Activities towards the Henry and Knoevenagel Reactions

The reactions of 3,3'-{(pyridine-2,6-dicarbonyl)bis(azanediyl)}dibenzoic acid (H2L) with zinc(II), cadmium(II), and samarium(III) nitrates were studied, and the obtained compounds, [Zn(1κO:2κO'-L)(H2O)2] n (1), [Cd(1κO 2:2κO 2-L)(H2O)2]2 ⋅6n H2O⋅ n C4H8O2 ⋅1.5n DMF (2), and [Sm(1κO:2κO'O'':3κO'''-L)(NO3)(H2O)(dmf)] n ⋅ n DMF (3), were characterized by elemental analysis, FTIR spectroscopy, thermogravimetric analysis, and X-ray single-crystal diffraction. Compounds 1 and 3 have 1D zigzag- and double-chain-type structures, respectively, whereas 2 features a dinuclear metallomacrocyclic complex. The ligand (L2-) orients in different conformations, that is, syn-syn for 1 and anti-anti for 2 and 3. Compound 1 is the first example in which the syn-syn conformation for this ligand has been observed. These compounds act as heterogeneous catalysts for the nitroaldol (Henry; in water medium) and Knoevenagel condensation reactions of different aldehydes, and the most effective is zinc coordination polymer 1. Recyclability, heterogeneity, and size-selectivity tests were performed, which showed that the catalyst was highly active over at least four recycling runs.

Crystal structure and Hirshfeld surface analysis of (E)-3-[(2,3-di-chloro-benzyl-idene)amino]-5-phenyl-thia-zolidin-2-iminium bromide

In the cation of the title salt, C16H14Cl2N3S+·Br-, the central thia-zolidine ring adopts an envelope conformation. The phenyl ring is disordered over two sites with a refined occupancy ratio of 0.541 (9):0.459 (9). In the crystal, C-H⋯Br and N-H⋯Br hydrogen bonds link the components into a three-dimensional network with the cations and anions stacked along the b-axis direction. Weak C-H⋯π inter-actions, which only involve the minor disorder component of the ring, also contribute to the mol-ecular packing. In addition, there are also inversion-related Cl⋯Cl halogen bonds and C-Cl⋯π (ring) contacts. A Hirshfeld surface analysis was conducted to verify the contributions of the different inter-molecular inter-actions.