Three crystal structures reported as lacking centers that should be refined as centrosymmetric

The compounds {[Fe(phen)₃]²⁺(TCNQ–TCNQ)²⁻) · 2(CH₃OH)} (FIWPRD), {[Fe(C₅H₅)(C₅H₄CH₂NMe₃)]⁺)(TCNQ⁻) (IKONOL), and {[Cu(1,4,5,12-tetraazacyclo-pentadecane)]²⁺(TCNQ⁻)₂} (AVOJEA) were reported in the non-centrosymmetric space groups Cc (#9), Pna2₁ (#33), and P1 (#1). Examination of the several sets of atomic coordinates shows that the space groups are more likely to be C2/c (#15), Pnma (#63), and (#2), respectively. Confirmation of the centrosymmetric models requires access to the diffraction intensities; unfortunately these are not in the public domain.

Modification of supramolecular assemblies based on C4H7(CH3)Te heterocycle and cooperative participation of intermolecular I···I, Te···I, Te···O secondary bonds; C(sp3)–H···O and C(sp2)–H···O hydrogen bonds

2-Methyl-1,1-dicarboxylato-1-telluracyclopentanes C₄H₇(CH₃)Te(OCOR)₂ (R=OCO, C₆H₅, 4-NO₂C₆H₄, 3,5-(NO₂)₂C₆H₃, C₆H₅CH=CH, 4-OCH₃C₆H₄) (2–7) were synthesised from the reactions of 2-methyl-1,1-diiodo-1-telluracyclopentane (1) and corresponding silver salts and characterised by (IR &¹HNMR) spectroscopy. The structures of C₄H₇(CH₃)TeI₂ (1), C₄H₇(CH₃)Te(OCOC₆H₅)₂ (3) and C₄H₇(CH₃)Te(4-NO₂C₆H₄OCO)₂ (4) were established by single crystal X-ray diffraction studies. The structures of 1, 3 & 4 (the immediate environment about tellurium is that of distorted trigonal bipyramidal geometry with a stereochemically active electron lone pair) are described in the context of their ability to generate intermolecular I···I, Te···I, Te···O secondary bonds; C(sp³)–H···O and C(sp²)–H···O hydrogen bonds leading to the formation of polymeric, tetrameric and trimeric supramolecular assemblies. The modification of supramolecular assembly present in the precursor 1 is demonstrated and the cooperative participation of C(sp²)–H···O & C(sp³)–H···O hydrogen bonds, probably, helpful in strengthening the supramolecular assembly is discussed.

Interaction of dicyclopentadienyl chloride complexes of yttrium and lutetium with sodium naphthalenide

The reaction of Cp₂LuCl with sodium naphthalenide gives an anionic hydride complex [(Cp₂LuH)₃H][Na(THF)₆] (1) and complex Cp₂Lu(2-C₁₀H₇)(THF) (2) containing a -bonded naphthyl ligand. The structure of1 was confirmed by X-ray analysis. When Cp₂YCl is used as the starting material, Cp₃Y and an anionic hydride complex also containing a -naphthyl ligand are formed. A reaction mechanism involving the formation of an unstable complex [(Cp₂Ln⁺)₂(C₁₀H² ₈-)] (4) and its fragmentation into hydride and -naphthyl species is proposed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 20–20, November, 1994.     

Effect of chelating agent on the oxidation rate of PCP in the magnetite/H2O2 system at neutral pH

The complex [Rh(CO)₂Cl]₂ reacts with two molar equivalent of pyridine carboxylic acids ligands Py-2-COOH(a), Py-3-COOH(b) and Py-4-COOH(c) to yield rhodium(I) dicarbonyl chelate complex [Rh(CO)₂(L^/)](1a) {L^/ = η²-(N,O) coordinated Py-2-COO⁻(a^/)} and non-chelate complexes [Rh(CO)₂ClL^//](1b,c) {L^// = η¹-(N) coordinated Py-3-COOH(b), Py-4-COOH(c)}. The complexes 1 undergo oxidative addition (OA) reactions with different electrophiles such as CH₃I, C₂H₅I, C₆H₅CH₂Cl and I₂ to give penta coordinated Rh(III) complexes of the types [Rh(CO)(CORⁿ)XL^/], {n = 1,2,3; R¹ = CH₃(2a); R² = C₂H₅(3a); X = I and R³ = CH₂C₆H₅ (4a); X = Cl}, [Rh(CO)I₂L^/](5a), [Rh(CO)(CORⁿ)ClXL^//] {R¹ = CH₃(6b,c); R² = C₂H₅(7b,c); X = I and R³ = CH₂C₆H₅ (8b,c); X = Cl} and [Rh(CO)ClI₂L^//](9b,c). The complexes have been characterized by elemental analysis, IR and ¹H NMR spectroscopy. Kinetic data for the reaction of 1a–b with CH₃I indicate a first order reaction. The catalytic activity of 1a–c for the carbonylation of methanol to acetic acid and its ester is evaluated and a higher turn over number (TON = 810–1094) is obtained compared with that of the well-known commercial species [Rh(CO)₂I₂]⁻ (TON = 653) at mild reaction conditions (temperature 130 ± 5 °C, pressure 35 ± 5 bar).     

The 20-Tungsto-4-Tellurate(IV) [H2Te4W20O80]22− and the 15-Tungstotellurate(IV) [NaTeW15O54]13−

The 20-tungsto-4-tellurate(IV) polyanion [H₂Te₄W₂₀O₈₀]^22? (1) has been synthesized and isolated in the form of its hydrated sodium salt Na₂₂[H₂Te₄W₂₀O₈₀]·64H₂O (Na-1). Na-1 has been characterized in the solid state by FTIR and TGA. Single-crystal X-ray diffraction analysis revealed that Na-1 crystallizes in the triclinic space group P ${\bar 1}The 20-tungsto-4-tellurate(IV) polyanion [H₂Te₄W₂₀O₈₀]²²⁻ (1) has been synthesized and isolated in the form of its hydrated sodium salt Na₂₂[H₂Te₄W₂₀O₈₀]·64H₂O (Na-1). Na-1 has been characterized in the solid state by FTIR and TGA. Single-crystal X-ray diffraction analysis revealed that Na-1 crystallizes in the triclinic space group P , with a = 12.741(2) ?, b = 16.842(3) ?, c = 17.197(4) ?, α = 93.961(10)°, β = 107.466(8)°, γ = 108.548(8)°, V = 3281.5(11) ?³ and Z = 1. The polyanion 1 comprises two [HTe₂W₁₀O₄₀]¹¹⁻ fragments, connected through Te−O–W μ₂-oxo bridges, and each containing a pair of face-shared WO₆ octahedra. Furthermore, the 15-tungstotellurate(IV) polyanion [NaTeW₁₅O₅₄]¹³⁻ (2) was synthesized and crystallized as a sodium salt in the orthorhombic space group Pccn, with a = 11.8841(5) ?, b = 20.8934(11) ?, c = 31.801(2) ?, V = 7896.3(7) ?³ and Z = 4. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Dedicated to Professor C. N. R. Rao on the occasion of his 75th birthday     

A mononuclear cobalt(II) hydroxo complex: synthesis,molecular structure,and reactivity studies

A novel Co(II) hydroxo complex Co{HB(3-^tBu-5-ⁱPrpz)₃}(OH) 4 {where HB(3-^tBu-5-ⁱPrpz)₃ = hydrotris(3-tert-butyl-5-isopropylpyrazol-l-yl)borate} has been prepared and its molecular structure has been determined by X-ray crystallography. This complex is mononuclear with distorted tetrahedral geometry. The reaction of CO₂ with Co{HB(3-^tBu-5-ⁱPrpz)₃}(OH) resulted in the formation of a μ-carbonato bridged binuclear complex [Co{HB(3-^tBu-5-ⁱPrpz)₃}]₂(CO₃) wherein the carbonate group is bound to both metal centers in an asymmetrical manner. In order to explore the role of labile metal complexes in promoting ester hydrolysis, complexes [Co{HB(3,5-ⁱPr₂pz)₃}]₂(OH)₂ and Co{HB(3-^tBu-5-ⁱPrpz)₃}(OH) have been used as catalysts in the hydrolysis of both carboxylate as well as phosphate esters. The product of 4-nitrophenylacetate hydrolysis with Co{HB(3-^tBu-5-ⁱPrpz)₃}(OH) was isolated as four coordinate Co{HB(3-^tBu-5-ⁱPrpz)₃}(OC₆H₄-4-NO₂) 6, whereas the reaction of 4-nitrophenyltrifluoroacetate with [Co{HB(3,5-ⁱPr₂pz)₃}]₂(OH)₂ resulted the formation of the six coordinate Co{HB(3,5-ⁱPr₂pz)₃}(OC₆H₄-4-NO₂)(MeCN)₂ species. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.

---

Hydrothermal Synthesis, Crystal Structures and Electrochemical Properties of Two Phosphatotungstates Containing Keggin Clusters, [Cu(2,2′-bipy)2]5[PW12O40] · 2H2O and (Hpip)3[PW12O40]

Two new phosphatotungstates containing Keggin clusters, [Cu(2,2′-bipy)₂]₅[PW₁₂O₄₀] · 2H₂O (1) (2,2′-bipy = 2,2′-bipyridine) and (Hpip)₃[PW₁₂O₄₀] (2) (pip = piperazine) have been hydrothermally synthesized and characterized by IR, element analysis and cyclic voltammogram. Compound 1 consists of one discrete Keggin polyanion [PW₁₂O₄₀]^5?, five isolated complex cations [Cu(2,2′-bipy)₂]⁺ and two water molecules. The organic moieties exhibit regular packing with offset aromatic–aromatic interactions between the bipys, leading to a compact supramolecular framework structure. Compound 2 is made up of one discrete Keggin polyanion [PW₁₂O₄₀]^3? and three pip cations. Compounds 1 and 2 were employed to fabricate bulk-modified carbon paste electrode to research on their electrochemistry properties. Their electrochemical behaviors and electrocatalysis that 1- and 2-CPEs have electrocatalytic activities toward the oxidation of nitrite. Compound 1 is in the orthorhombic system, space group Pna2₁, with a = 28.1928(9), b = 21.5479(6), c = 19.9088(6) Å, V = 12,094.5(6) Å³ and Z = 4. Compound 2 is in the rhombohedral system, space group R $ \overline{3} Two new phosphatotungstates containing Keggin clusters, [Cu(2,2′-bipy)₂]₅[PW₁₂O₄₀] · 2H₂O (1) (2,2′-bipy = 2,2′-bipyridine) and (Hpip)₃[PW₁₂O₄₀] (2) (pip = piperazine) have been hydrothermally synthesized and characterized by IR, element analysis and cyclic voltammogram. Compound 1 consists of one discrete Keggin polyanion [PW₁₂O₄₀]⁵⁻, five isolated complex cations [Cu(2,2′-bipy)₂]⁺ and two water molecules. The organic moieties exhibit regular packing with offset aromatic–aromatic interactions between the bipys, leading to a compact supramolecular framework structure. Compound 2 is made up of one discrete Keggin polyanion [PW₁₂O₄₀]³⁻ and three pip cations. Compounds 1 and 2 were employed to fabricate bulk-modified carbon paste electrode to research on their electrochemistry properties. Their electrochemical behaviors and electrocatalysis that 1- and 2-CPEs have electrocatalytic activities toward the oxidation of nitrite. Compound 1 is in the orthorhombic system, space group Pna2₁, with a = 28.1928(9), b = 21.5479(6), c = 19.9088(6) ?, V = 12,094.5(6) ?³ and Z = 4. Compound 2 is in the rhombohedral system, space group Rc, with a = 17.9191(5), c = 23.7439(9) ?, V = 6,602.6(4) ?³ and Z = 6. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Crystal structures and theoretical calculations of trans-2,4,4-trimethyl-4-silathiane 1-oxide and 4,4-dimethyl-4-silathiane 1,1-dioxide

The crystal and molecular structures of trans-2,4,4-trimethyl-4-silathiane 1-oxide 1 and 4,4-dimethyl-4-silathiane 1,1-dioxide 2 were determined by single crystal X-ray diffraction. Both compounds have the chair conformation with the 2-Me and the S=O group in compound 1 occupying the equatorial positions. The DFT (B3LYP/6-311G(d,p)) and MP2 (MP2/6-311G(d,p)) theoretical calculations nicely reproduce the X-ray experimental geometry. The obtained results are discussed in connection with the electronic and structural properties of the compounds.

Luminescent Properties of Hexanuclear Molybdenum(II) Chloride Clusters Containing Thiolate Ligands

The emission spectra of a series of molybdenum(II) chloride clusters containing thiolate ligands, [Mo₆(μ₃-Cl)₈(SR)₆]²⁻ (R = Et, Bu, Ph, Bn), have been recorded. These complexes all show a broad emission at ~700 nm after excitation at 337, 400 and 410 nm. Determination of the excited state lifetimes and quantum yields of these complexes in acetonitrile reveals that (Bu₄N)₂[Mo₆(μ₃-Cl)₈(SPh)₆] displays the longest excited state lifetime of this series (26 μs at 296 K).

Molecular and crystal structure of ethylene acetal of <Emphasis Type="Italic">endo</Emphasis>-<Emphasis Type="Italic">endo</Emphasis>-3-trityloxymethylbicyclo[3.3.1]nonane-2-on-7-ol

Molecular structure of ethylene acetal of 3-trityloxymethylbicyclo[3.3.1]nonane-2-on-7-ol (3) was determined by X-ray investigation. It was revealed that 3 has endo-endo-configuration and adopt chair-boat-conformation. The distortion of rings was evaluated by calculation of the Zefirov–Palyulin and Cremer–Pople puckering parameters. Failure of esterification of 3 was rationalized in terms of steric hindrance and intramolecular hydrogen bonding.

Nonlinear magneto-optical effects and photomagnetism of electrochemically synthesized molecule-based magnets

This article describes novel optical functionalities such as photomagnetic effects and magnetization-induced second harmonic generation (MSHG) in several cyano-bridged metal assemblies. Single crystal- and film-types of a cyano-bridged Cu–Mo bimetallic assembly, , were electrochemically prepared. When this compound was irradiated with light, spontaneous magnetization with a Curie temperature (T _C) of 23 K was observed. Electrochemically prepared Fe^II[Cr^III(CN)₆]_2/3·5H₂O thin film, which was a ferromagnet with T _C=21 K, showed photoreduced magnetization. This photomagnetism is due to the change of ferromagnetic coupling between Fe^II and Cr^III. MSHG was observed in Cs^ICo^II[Cr^III(CN)₆]·0.5H₂O. This -type Prussian blue analog-based magnet is proven to be a piezoelectric ferromagnet, i.e., condensed matter with both piezoelectric and ferromagnetism. This MSHG is due to the coupling between a piezoelectric structure of and ferromagnetism with a T _C of 46 K.

Synthesis and dopamine receptor binding affinity of 4H-thiochromenoapomorphines

Abstract  The synthesis of 4H-thiochromene derivatives of apomorphines, a novel class of isoquinoline alkaloid-related compounds, has been achieved by different O-dealkylation methods applied on previously published heteroring-fused aporphinoids. Detailed DFT study has been presented regarding the mechanism of the L-selectride-mediated multiple O-dealkylation of a seven-ring aporphine analogue. Dopamine-binding tests confirmed the essential function of 11-hydroxy moiety of the aporphine skeleton and revealed a remarkable D₁ over D₂ specificity for the derivative having the 4H-thiochromene ring system attached to positions 2 and 3 of the aporphine backbone. Graphical Abstract  

CAL3JHH: a Java program to calculate the vicinal coupling constants (<Superscript>3</Superscript><Emphasis Type="Italic">J</Emphasis><Subscript>H,H</Subscript>) of organic molecules

Here, we present a free web-accessible application, developed in the JAVA programming language for the calculation of vicinal coupling constant (³ J _H,H) of organic molecules with the H–C_sp3–C_sp3–H fragment. This JAVA applet is oriented to assist chemists in structural and conformational analyses, allowing the user to calculate the averaged ³ J _H,H values among conformers, according to its Boltzmann populations. Thus, the CAL3JHH program uses the Haasnoot–Leeuw–Altona equation, and, by reading the molecule geometry from a protein data bank (PDB) file format or from multiple pdb files, automatically detects all the coupled hydrogens, evaluating the data needed for this equation. Moreover, a “Graphical viewer” menu allows the display of the results on the 3D molecule structure, as well as the plotting of the Newman projection for the couplings. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.

Hypervalence and the delocalizing versus localizing propensities of H 3– , Li 3– , CH 5– and SiH 5–

Lithium and silicon have the capability to form hypervalent structures, such as Li₃^– and SiH₅^–, which is contrasted by the absence of this capability in hydrogen and carbon, as exemplified by H₃^– and CH₅^– which, although isoelectronic to the former two species, have a distortive, bond-localizing propensity. This well-known fact is nicely confirmed in our DFT study at BP86/TZ2P. We furthermore show that the hypervalence of Li and Si neither originates from the availability of low-energy 2p and 3d AOs, respectively, nor from differences in the bonding pattern of the valence molecular orbitals; there is, in all cases, a 3-center-4-electron bond in the axial X–A–X unit. Instead, we find that the discriminating factor is the smaller effective size of C compared to the larger Si atom, and the resulting lack of space around the former. Interestingly, a similar steric mechanism is responsible for the difference in bonding capabilities between H and the effectively larger Li atom. This is so, despite the fact that the substituents in the corresponding symmetric and linear dicoordinate H₃^– and Li₃^– are on opposite sides of the central atom. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.

Crystal structure of olanzapine and its solvates. Part 3. Two and three-component solvates with water, ethanol, butan-2-ol and dichloromethane

Crystalline solvates of olanzapine (1), 2-methyl-4-(4-methyl-1-piperazinyl)-10H-thieno[2,3-b][1,5]benzodiazepine, have been characterized by an X-ray analysis and thermal (DSC) data. Crystallization of 1 from ethanol gives a solid containing both water and ethanol molecules; the solvate 1 · H₂O · EtOH (2:2:1) is monoclinic with the space group P2₁/c and the unit-cell volume V = 3752.8(12) Å³. Butan-2-ol forms with 1 solvate which is also a three-component phase, 1 · H₂O · BuOH, but its stoichiometry is different (1:1:1). The space group for this crystal is P2₁/c and the unit-cell volume V = 2216.5(7) Å³. Crystalline olanzapine dichloromethane solvate (2:1), 1 · CH₂Cl₂, is triclinic with the space group .The characteristic feature of all crystal structures is presence of a pair of olanzapine molecules which form dimer stabilized by multiple weak C–Hπ interactions between the N-methylpiperazine fragment and the phenyl / thiophene systems. Theoretical calculations have been performed indicating that the total C–Hπ binding energy is about 8 kcal mol⁻¹. In the crystal structure, the self-assembled olanzapine molecular dimers are arranged into parallel crystal planes. Packing of the layers proceeds in two ways in which structural motives are replicated by (i) perpendicular translation forming columns, and (ii) rotation around the twofold screw axis (parallel to the layer).     

On the open-circuit interaction between methanol and oxidized platinum electrodes

In the present work, results of the interaction between methanol and oxidized platinum surfaces as studied via transients of open-circuit potentials are presented. The surface oxidation before the exposure to interaction with 0.5 M methanol was performed at different polarization times at 1.4 V vs reversible hydrogen electrode (RHE). In spite of the small changes in the initial oxide content, the increase of the pre-polarization time induces a considerable increase of the time needed for the oxide consumption during its interaction with methanol. The influence of the identity of the chemisorbing anion on the transients was also investigated in the following media: 0.1 M HClO₄, 0.5 M H₂SO₄, and 0.5 M H₂SO₄ + 0.1 mM Cl⁻. It was observed that the transient time increases with the energy of anion chemisorption and, more importantly, without a change in the shape of the transient, meaning that free platinum sites are available at the topmost layer all over the transient and not only in the potential region of small oxide ‘coverage’. The impact of the pre-polarization time and the effect of anion chemisorption on the transients are rationalized in terms of the presence of surface and subsurface oxygen driven by place exchange.

Molybdenum(VI) network polymers based on anion–π interaction and hydrogen bonding: Synthesis, crystal structures and oxidation catalytic application

A crystallographic investigation of anion–π interactions and hydrogen bonds on the preferred structural motifs of molybdenum(VI) complexes has been carried out. Two molybdenum(VI) network polymers MoO₂F₄·(Hinca)₂ (1) and MoO₂F₃(H₂O)·(Hinpa) (2), where inca = isonicotinamide and inpa = isonipecotamide, have been synthesized, crystallographically characterized and successfully applied to alcohol oxidation reaction. Complex 1 crystallizes in the monoclinic space C2/c: a = 16.832(3) Å, b = 8.8189(15) Å, c = 12.568(2) Å, β = 118.929(3)°, V = 1560.1(5) Å³, Z = 4. Complex 2 crystallizes in the triclinic space P-1: a = 5.459(2) Å, b = 9.189(4) Å, c = 12.204(5) Å, α = 71.341(6)°, β = 81.712(7)°, γ = 77.705(7)°, V = 564.8(4) Å³, Z = 2. Complex 1 consists of hydrogen bonding and anion–π interactions, both of which are considered as important factors for controlling the geometric features and packing characteristics of the crystal structure. The geometry of the sandwich complex of [MoO₂F₄]²⁻ with two pyridine rings indicates that the anion–π interaction is an additive and provides a base for the design and synthesis of new complexes. For complex 2, the anions and the protonated inpa ligands form a 2D supramolecular network by four different types of hydrogen contacts (N–HF, N–HO, O–HF and O–HO). The catalytic ability of complexes 1 and 2 has also been evaluated by applying them to the oxidation of benzyl alcohol with TBHP as oxidant.     

Mesogenic and magnetic behavior in cobalt(II) and iron(II) compounds with long alkyl chains

Abstract  Metal complexes with long alkyl chains [Co(C16-terpy)₃](BF₄)₂ (1), [Fe(C16-terpy)₂](BF₄)₂ (2), [Co(C16-terpy)₂](BPh₄)₂ (3), [Co(C14-terpy)₂](BF₄)₂ (4), and [Fe(C12C10C5-terpy)₂](BF₄)₂ (5) were synthesized and their physical properties characterized, where C16-terpy, C14-terpy, and C12C10C5-terpy are 4′-hexadecyloxy-2,2′:6′,2′′-terpyridine, 4′-tetradecyloxy-2,2′:6′,2′′-terpyridine, and 4′-5′′′-decyl-1′′′-heptadecyloxy-2,2′:6′,2″-terpyridine, respectively. Complexes 1, 2, and 5 exhibited liquid–crystal properties in the temperature ranges of 371–528 K and 466–556 K, and 88–523 K, respectively. Variable-temperature magnetic susceptibility measurements revealed that the Co(II) complexes 1 and 4 exhibited unique spin transitions (T _1/2↓ = 217 K and T _1/2↑ = 260 K for 1 and T _1/2↓ = 250 K and T _1/2↑ = 307 K for 4), so-called ‘reverse spin transition,’ induced by structural phase transitions. Complex 3 exhibited gradual spin-crossover behavior (T _1/2 = 160 K.), and complex 5 exhibited spin transitions (T _1/2↑ = 288 K and T _1/2↓ = 284 K) at the liquid crystal transition temperature. Compounds with multifunction, i.e., magnetic and liquid–crystal properties, are important in the development of molecular materials. Graphical Abstract  

[(η-C6H6)Ru(L)(Cl/N3/CN/CH3CN)] complexes of non-planar pyrazolylmethylpyridine ligands: Formation of helices due to C-H?X (X = Cl, N) interaction

Structural analysis of a previously reported half-sandwich complex having three-legged “piano-stool” geometry [(η⁶-C₆H₆)Ru^II(L¹)Cl][PF₆] (1) (L¹ = 2-(pyrazol-1-ylmethyl)pyridine) is described. Treatment of 1 with (i) Ag(CF₃SO₃) in CH₃CN and (ii) NaN₃ in CH₃OH, and (iii) the reaction between [(η⁶-C₆H₆)Ru(L²)Cl]-[PF₆] (2) (previously reported) and NaCN in C₂H₅OH led to the isolation of [(η⁶-C₆H₆)Ru(L¹)(CH₃CN)][PF₆]₂ (3), [(η⁶-C₆H₆)Ru(L¹)(N₃)][PF₆] (4), and [(η⁶-C₆H₆)Ru(L²)(CN)][PF₆] (5), respectively (L² = 2-(3,5-dimethyl-pyrazol-1-ylmethyl)pyridine). The complex [(η⁶-C₆H₆)Ru(L⁴)Cl][PF₆] (6) with a new ligand (L⁴ = 2-[3-(4-fluorophenyl)pyrazol-1-ylmethyl]pyridine) has also been synthesized. The structures of 3-6 have been elucidated (¹H NMR spectra; CD₃CN). The molecular structures of 1, 4, and 6·C₆H₅CH₃ have been determined. Notably, the crystal-packing in these structures is governed by C-H?X (X = Cl, N) interactions, generating helical architectures.