Bis(1‐methyl­guanidinium) tetra­chloro­cuprate(II) and 4‐(2‐pyrimidin‐1‐io)­piperazinium tetra­chloro­cuprate(II)

The crystal structures of the title compounds, (C₂N₃H₈)₂[CuCl₄], (I), and (C₈H₁₄N₄)[CuCl₄], (II), have been studied by X‐ray diffraction. The structures consist of discrete [CuCl₄]^2? anions with two monoprotonated (C₂N₃H₈)⁺ cations for (I) and a diprotonated (C₈N₄H₁₄)²⁺ cation for (II). The [CuCl₄]^2? anions of both compounds have flattened tetrahedral geometries. There are several N—H?Cl weak bonds that join the [CuCl₄]^2? anions and the organic cations helping retain the pseudo‐tetrahedral geometries of the anions.     

4,4′‐Thio­dipyridinium tetra­chloro­copper(II)

The title compound, (C₁₀H₁₀N₂S)[CuCl₄], was obtained by the reaction of cupric chloride with pyridine‐4‐thiol in a mixture of aceto­nitrile and tetra­hydro­furan, suggesting that the desulfurization and coupling reactions of pyridine‐4‐thiol occurred in the presence of the Cu²⁺ ion. X‐ray diffraction analysis reveals the presence of one 4,4′‐thio­dipyridinium cation, H₂bps²⁺, and one [CuCl₄]²⁻ anion. The cations interact with the anions via N—H⋯Cl hydrogen‐bonding interactions to form a closed `chair' conformation.     

Chloro­(3,6,13,16‐tetraethyl‐2,7,12,17‐tetra­methyl­porphycenato‐κ4N)iron(III) chloro­form solvate

The X‐ray crystallographic analysis of the title complex, chloro­[3,10,13,20‐tetraethyl‐4,9,14,19‐tetra­methyl­penta­cyclo[16.2.1.1^2,5.1^8,11.1^12,15]­tetracosa‐2,4,6,8(23),9,12,14,16,18(21),19‐decaene]­iron(III) chloro­form solvate, [Fe(C₃₃H₃₇N₄)Cl]·CHCl₃, reveals a twisted macrocyclic framework with a slightly distorted rectangular pyramidal core, where the deviation of the central Fe^III atom from the least‐squares plane of the C₂₀N₄ core is 0.594 (1) Å. Some important bond distances are as follows: Fe—N 2.019 (3), 2.026 (3), 2.028 (3) and 2.034 (3) Å; Fe—Cl 2.232 (1) Å.     

One‐dimensional structure of catena‐poly[tetra­ethyl­ammonium [tetra­cyano­iron(III)‐μ‐cyano‐[bis­(ethyl­ene­diamine)­cadmium(II)]‐μ‐cyano] tetra­hydrate]

The title compound, {(C₈H₂₀N)[CdFe(CN)₆(C₂H₈N₂)₂]·4H₂O}_n, was isolated from the aqueous system Cd²⁺/ethyl­ene­diamine (en)/[Fe(CN)₆]³⁻ in the presence of [Et₄N]Br. The crystal structure is dominated by a one‐dimensional motif, viz. a negatively charged 2,2‐CT (cis–trans) [–Cd(en)₂—NC—Fe(CN)₄—CN–]_nⁿ⁻ chain. The Cd and Fe atoms of the anion and the N atom of the cation all lie on twofold axes. The ethyl groups of the cation are equally disordered over two orientations. The cationic building block of the chain consists of a Cd^II atom coordinated by two chelating en ligands, and the distorted octa­hedral coordination is completed by two bridging cyano ligands in cis positions. The anionic building block is an [Fe(CN)₆]³⁻ anion in which the Fe^III atom is octa­hedrally coordinated by six cyano ligands; two of the cyano ligands, in trans positions, are bridging. The uncoordinated water mol­ecules link neighbouring chains through O—H⋯N and N—H⋯O hydrogen bonds.     

Bis(6‐thioxo‐1,6‐dihydro­purinium) tetra­chloro­zincate(II)

The title salt, (C₅H₅N₄S)₂[ZnCl₄], consists of two 6‐thioxo‐1,6‐dihydro­purinium (6mpH₂⁺) cations (A and B) and a tetra­chloro­zincate anion, which are held together by N—H⋯Cl and C—H⋯Cl inter­actions. There is an anion–π inter­action between one Cl atom of the [ZnCl₄]⁻ anion and the pyrimidine ring of the 6mpH₂⁺(B) cation. Inter­molecular π–π stacking inter­actions allow 6mpH₂⁺(A) cations to form anti­parallel pairs. One inter­esting structural feature is the double N—H⋯N inter­molecular hydrogen bonds between two 6mpH₂⁺(A) cations. This kind of inter­action, mimicking that of natural nucleobases, can be very valuable in designing new therapeutic purine derivatives.     

Bis(2‐amino‐6‐methyl­pyridinium) tetra­chloro­zincate(II)

The title compound, (C₆H₉N₂)₂[Zn^IICl₄], consists of two 2‐amino‐6‐methyl­pyridinium (AMP) cations and one [ZnCl₄]²⁻ anion, which are held together by N—H·Cl hydrogen bonds. Bond lengths within the AMP cation indicate that the imine tautomer makes a significant contribution to the structure. The mol­ecules are associated by two different π–π interactions between identical antiparallel AMP cations, with face‐to‐face distances of 3.627 (4) and 3.342 (3) Å, to form a one‐dimensional chain.     

Astemizole tetra­chloro­cuprate(II)

The structure of {3‐[(4‐fluoro­phenyl)­methyl]‐1H‐benzimidazol‐2‐ylidene}{1‐[2‐(4‐meth­oxy­phenyl)­ethyl]‐4‐piperidin‐1‐io}ammonium tetra­chloro­cuprate(II), (C₂₈H₃₃FN₄O)[CuCl₄], contains diprotonated cations of astemizole hydrogen bonded to three Cl atoms in two different CuCl₄^2? anions, with Cl?N distances in the range 3.166 (4)–3.203 (4) Å. The geometry around copper is flattened tetrahedral with significantly different Cu—Cl distances which lie in the range 2.1968 (14)–2.2861 (12) Å. The phenyl­ethyl C atoms of the (4‐methoxy­phenyl­)ethyl group are disordered indicating the presence of two conformers in the crystals.     

trans‐Tetra­chloro­bis(4‐methyl­pyridine)­germanium(IV)

The structure of the title compound, [GeCl₄(C₆H₇N)₂], (I), is the first example of an addition compound of GeCl₄ with two aromatic nitro­gen bases. The mol­ecule, with essential D_2h symmetry, has crystallographic C_2h symmetry. The environment around the Ge atom can be described as a slightly distorted octahedron with the 4‐methyl­pyridine ligands occupying axial positions and the four chloro ligands in the equatorial plane. The structure of (I) is isomorphous with the corresponding silicon halides.     

μ‐Oxo‐bis­[(2,3,12,13‐tetra­bromo‐5,10,15,20‐tetra­phenyl­porphyrinato)­iron(III)] bis­(di­chloro­methane) solvate

The precise structure of the title compound, [Fe₂O(C₄₄H₂₄Br₄N₄)₂]·2CH₂Cl₂, is reported. The Fe—N distances are non‐equivalent in pairs because of the asymmetric peripheral substitution; the values are 2.098 Å to the brominated rings and 2.041 Å to the other two rings. The Fe—O bond distance is 1.7583 (4) Å. The mol­ecule has required twofold symmetry so that there is one unique porphyrin macrocycle and one Fe—O bond length in contrast to a previous report on the same species.     

cis‐Dinitrito(1,4,8,11‐tetra­aza­cyclo­tetra­decane‐κ4N)­chromium(III) nitrite

In the title compound, [Cr(ONO)₂(cyclam)]NO₂ (cyclam is 1,4,8,11‐tetra­aza­cyclo­tetra­decane, C₁₀H₂₄N₂), the complex cation is located on a twofold symmetry axis. The central Cr atom has a distorted octahedral coordination, involving two Cr—O bonds, with the monodentate nitrite O atoms adopting a cis configuration, and four Cr—N bonds. The mean Cr—N and Cr—O distances are 2.0895 (14) and 1.9698 (14) Å.     

A cobalt(III) compound of a 13‐membered cyclic tetra­amine: trans‐(12,12‐dimethyl‐1,4,7,10‐tetra­aza­cyclo­tetra­decane)diisothio­cyanato­cobalt(III) tetra­isothio­cyanato­zinc(II) ethanol solvate

The title compound, [Co(NCS)₂(C₁₁H₂₆N₄)]₂[Zn(NCS)₄]·C₂H₅OH, has two similar cations with the Co^III atom coordinated in a planar fashion by the 13‐membered cyclic tetra­amine, in the 1R,4S,7R,10S configuration, and with trans isothio­cyanate ligands. The six‐membered chelate ring is in a chair conformation, with one axially and one equatorially oriented methyl substituent [mean Co—N = 1.948 (2) Å]. The `opposite' chelate ring (N<sup>4</sup> and N<sup>7</sup>) is in an eclipsed conformation [mean Co—N = 1.928 (2) Å], and the `side' chelate rings have gauche conformations. The mean Co—N_NCS distance is 1.928 (2) Å. Both cations have one Co—N—C group nearly linear and the other appreciably bent, with mean Co—N—C angles of 178.7 (1) and 160.4 (1)°, respectively. The [Zn(NCS)₄]²⁻ anion is approximately tetra­hedral, with Zn—N = 1.951 (1)–1.986 (1) Å, N—Zn—N = 104.5 (1)–111.9 (1)° and Zn—N—C = 152.5 (1)–179.4 (1)°. One NH group is hydrogen bonded to the ethanol O atom and the other NH groups are bonded to thio­cyanate S atoms, forming a network.     

3‐Methylamido‐3′,4′‐ethyl­enedithiotetra­thia­fulvalene­(+) potassium tetra­isothio­cyanato­mercury(II)

In the title compound, (C₁₀H₉NOS₆)K[Hg(SCN)₄] or (EDT–TTF–CONHMe)K[Hg(SCN)₄)], fully oxidized organic (EDT–TTF–CONHMe)^+· radical cations form quasi‐one‐dimensional stacks running along the monoclinic 2₁ axis and alternating along the crystallographic [101] direction with inorganic anion stacks made from mixed K⁺–[Hg(SCN)₄]²⁻ ribbons. For each anion, three essentially collinear SCN ligands inter­act with the K⁺ ions via short N⋯K contacts, while the terminal N atom of the fourth SCN group is engaged in a number of hydrogen‐bond contacts with the –CH, –NH and –CH₂ hydrogen‐bond donors of the amide function. Radical cations are dimerized along the stacks and the crystal conductivity is activated.     

trans‐Di­chlorotetrakis(4‐methyl­pyridine)­silicon bis­(triiodide) chloro­form solvate

At 173 K, the dication of the title compound, C₂₄H₂₈Cl₂N₄Si²⁺·2I₃^?·CHCl₃, is located on a crystallographic fourfold rotation axis. The chloro ligands occupy axial positions and the four 4‐methyl­pyridine ligands lie in the equatorial plane. The almost linear I₃^? ion is located on a crystallographic mirror plane and displays two significantly different I—I bond lengths. Furthermore, chloro­form mol­ecules, which are disordered about a centre of inversion, fill the remaining gaps in the crystal structure.     

A complex containing both five‐ and six‐coordinate [bis(5‐bromosalicyli­dene)benzene‐1,2‐diimine]chloro­iron(III)

The title compound, aqua­chloro{4,4′‐di­bromo‐2,2′‐[o‐phenylenebis­(nitrilo­methyl­idyne)]­diphenolato‐O,N,N′,O′}iron(III)–chloro{4,4′‐di­bromo‐2,2′‐[o‐phenyl­enebis­(nitrilomethyli‐dyne)]diphenolato‐O,N,N′,O′}iron(III)–di­methyl­form­amide (1/1/1), [FeCl(C₂₀H₁₂Br₂N₂O₂)][FeCl(C₂₀H₁₂Br₂N₂O₂)(H₂O)]·C₃H₇NO, contains one independent five‐coordinate [FeCl(C₂₀H₁₂Br₂N₂O₂)] monomer, one six‐coordinate [FeCl(C₂₀H₁₂Br₂N₂O₂)(H₂O)] monomer and a non‐coordinating di­methyl­form­amide solvent mol­ecule in the asymmetric unit. In the five‐coordinate monomer, the Fe atom shows distorted square‐pyramidal geometry, with the N and O atoms of the ligand at the base and the Cl atom at the apex of the pyramid. In the six‐coordinate monomer, the Fe atom is in a distorted octahedral geometry and coordinated by the donor atoms of the tetrafunctional ligand in the horizontal plane, and the coordination sphere is completed by the O atom of the water mol­ecule and the Cl atom at the axial positions. The title compound contains intermolecular O—H?O hydrogen bonds. Apart from these hydrogen bonds, there are also intermolecular C—H?Cl and C—H?O contacts.     

trans‐Bis(2,2‐diphenyl­ethyl­amine‐κN)bis­(5,5‐diphenyl­hydantoinato‐κN3)copper(II) and its chloro­form disolvate

The crystal structures of the title compounds, [Cu(C₁₅H₁₁N₂O₂)₂(C₁₄H₁₅N)₂] and [Cu(C₁₅H₁₁N₂O₂)₂(C₁₄H₁₅N)₂]·2CHCl₃, respectively, have been determined. The red disolvate complex affords a square‐planar CuN₄ coordination environment in which the Cu^II atom lies on a centre of symmetry. The blue solvent‐free complex affords a distorted square‐pyramidal CuN₄O coordination environment and adjacent mol­ecules form centrosymmetric dimers. A comparison of the different crystal structures focuses on the role of the solvent mol­ecules in supramolecular assemblies of the copper(II) complexes.     

2,6‐Bis(1‐benzyl‐1H‐1,2,3‐triazol‐4‐yl)pyridine and its octahedral copper complex

In the tridentate ligand 2,6‐bis(1‐benzyl‐1H‐1,2,3‐triazol‐4‐yl)pyridine, C₂₃H₁₉N₇, both sets of triazole N atoms are anti with respect to the pyridine N atom, while in the copper complex aqua[2,6‐bis(1‐benzyl‐1H‐1,2,3‐triazol‐4‐yl)pyridine](pyridine)(tetrafluoroborato)copper(II) tetrafluoroborate, [Cu(BF₄)(C₅H₅N)(C₂₃H₁₉N₇)(H₂O)]BF₄, the triazole N atoms are in the syn–syn conformation. The coordination of the Cu^II atom is distorted octahedral. The ligand structure is stabilized through intermolecular C—H...N interactions, while the crystal structure of the Cu complex is stabilized through water‐ and BF₄‐mediated hydrogen bonds. Photoluminiscence studies of the ligand and complex show that the ligand is fluorescent due to triazole–pyridine conjugation, but that the fluorescence is quenched on complexation.     

Bis­[tris­(ethyl­enedi­amine)­cobalt(III)] di­chloro­bis­[μ‐(1‐hydroxy­ethyl­idene)­di­phospho­nato(4–)]­di­ruthenium(II,­III)­(Ru–Ru) chloride trihydrate

In the title compound, [Co(C₂H₈N₂)₃]₂[Ru₂(C₂H₄O₇P₂)₂Cl₂]Cl·3H₂O, the building unit contains two crystallographically independent dinuclear [Ru₂(hedp)₂Cl₂]⁵⁻ anions, where hedp [viz. (1‐hydroxy­ethyl­idene)­di­phospho­nate] serves as a bis‐chelating bridging ligand, two types of [Co(en)₃]³⁺ cations, one uncoordinated Cl⁻ anion and five water mol­ecules of crystallization. The [Ru₂(hedp)₂Cl₂]⁵⁻ anions are connected to one another, forming one‐dimensional chains along the a axis. The [Co(en)₃]³⁺ cations are located between these chains and lie across inversion centres. An extensive series of hydrogen bonds lead to the formation of a three‐dimensional supramol­ecular network structure, with channels generated along the [100] direction. The uncoordinated water mol­ecules and Cl⁻ anions reside in these channels.     

An oxo‐centred trinuclear FeIII complex: tri­aqua­hexakis(μ2‐betaine‐O:O′)‐μ3‐oxo‐triiron(III) bis­(tetra­chloro­manganate) trichloride ­hexahydrate

The title compound, [Fe₃(C₅H₁₁NO₂)₆O(H₂O)₃](MnCl₄)₂Cl₃·6H₂O, contains a triiron core linked by a μ₃‐bridging oxide ion. Each of the iron(III) ions has a distorted octahedral environment, being coordinated, in addition to the oxide ion, by four neutral betaine mol­ecules and one water mol­ecule. The N‐alkyl­ated α‐amino acid betaine is present in the dipolar zwitterionic form and chelates pairs of Fe atoms at the vertices of the triangular [Fe₃O]⁷⁺ ionic core. The Fe complex has a crystallographically imposed D3 symmetry. The water mol­ecules fully exhaust their potential as hydrogen donors, forming a two‐dimensional hydrogen‐bond network in planes parallel to (001).     

Benzoin 4‐ethyl­thio­semicarbazone

In the title compound, 2‐hydr­oxy‐1,2‐diphenyl­ethanone 4‐ethyl­thio­semicarbazone, C₁₇H₁₉N₃OS, the thio­semi­carbazone moiety is planar and has an E configuration. The planar phenyl rings make dihedral angles of 82.34 (8) and 8.07 (17)° with the plane of the thio­semicarbazone moiety. The crystal structure contains two intra­molecular (N—H⋯O and N—H⋯N) and one inter­molecular inter­action (O—H⋯S), as well as two C—H⋯π(benzene) inter­actions. Mol­ecules are stacked in columns running along the a axis. Mol­ecules in each column are connected to each other by means of linear O—H⋯S hydrogen bonds and C—H⋯π inter­actions. In addition, there are also C—H⋯π(benzene) inter­actions between the columns.     

Cis‐ and trans‐bis(2‐cyano­ethyl­sulfan­yl)(decane‐1,10‐diyldithio)tetra­thia­fulvalene

The isomeric title compounds, 2,7‐bis(2‐cyanoethylsulfanyl)‐3,6‐(decane‐1,10‐diyldithio)tetrathiafulvalene and 2,6‐bis­(2‐cyanoethylsulfanyl)‐3,7‐(decane‐1,10‐diyldithio)­tetra­thiafulvalene, both C₂₂H₂₈N₂S₈, comprise bis­(2‐cyano­ethyl­sulfan­yl)tetra­thia­fulvalene units tethered by a saturated deca­methyl­enedithio linker attached in either a cis or a trans manner. The tetra­thia­fulvalene (TTF) group is planar in the cis isomer, but distorted significantly from planarity and twisted about its long axis in the trans isomer. In both structures, inter­molecular inter­actions are segregated into regions in which TTF units are brought into close contact and regions where the polymethyl­ene chains are brought into close contact. In the cis isomer, TTF units exhibit π–π stacking inter­actions, while in the trans isomer they do not.