Synthesis and Structural Characterization of Substituted Salicylate Titanocene Complexes: Three Supramolecular Frameworks Determined by Weak Interactions

Abstract  Based on the reaction between Cp₂TiCl₂ and substituted salicylic acids in the presence of β-cyclodextrin polymer (β-CDP), three four-coordinated titanocene complexes [(η⁵-C₅H₅)₂Ti(S,O′)(OCC₆H₄)·(C₆H₆)_0.5] (1), [(η⁵-C₅H₅)₂Ti{(O,O′)(3,5-Cl₂-OCC₆H₂)}] (2) and [(η⁵-C₅H₅)₂Ti{(O,O′)(3,5-(NO₂)₂-OCC₆H₂)}] (3) were synthesized in high yields and their crystal structures have been determined by single-crystal X-ray diffraction. The structure of 1 has a Monoclinic space group P2₁/c with a = 8.313(3) ?, b = 9.960(4) ?, c = 22.330(8) ?, β = 111.856(11)° and Z = 4. The structure of 2 has a Monoclinic space group P2₁/c with a = 8.0577(13) ?, b = 8.9022(14) ?, c = 21.977(4) ?, β = 96.298(3)° and Z = 4. The structure of 3 has a Triclinic space group P-1 with a = 8.1687(11) ?, b = 8.3027(11) ?, c = 12.7164(17) ?, α = 102.930(2)°, β = 100.479(2)°, γ = 95.458(2)° and Z = 2. Each of the complexes exhibits a three-dimensional framework constructed through weak interactions, which are hydrogen bonding, π–π stacking and C–H···π interactions. It was found that the variation of the substituted salicylate ligands affect the weak interactions as well as the specific framework structure that forms. Graphical Abstract  Three four-coordinated titanocene complexes [(η⁵-C₅H₅)₂Ti(S,O′)(OCC₆H₄)·(C₆H₆)_0.5] (1), [(η⁵-C₅H₅)₂Ti{(O,O′)(3,5-Cl₂-OCC₆H₂)}] (2) and [(η⁵-C₅H₅)₂Ti{(O,O′)(3,5-(NO₂)₂-OCC₆H₂)}] (3) were synthesized in high yields, each of the complexes exhibits a three-dimensional framework constructed through weak interactions. It was found that simple variation of the substituted salicylate ligands affect the weak interactions as well as the specific framework structure that forms. .     

Synthesis and Crystal Structure of Three New Metal-Organic Frameworks in the Ln(III)/2,6-Pyridinedicarboxylate System

Abstract  

In this paper, three new metal-organic frameworks, synthesized by hydrothermal technique, are described. The compounds crystallize in triclinic space group P − 1 with cell parameters, respectively equal to (1) [La(H₂O)₃(dipic)]₂(C₂O₄) · 2H₂O a = 7.9990(1) ?, b = 8.3380(4) ?, c = 9.6180(5) ?, α = 98.194(5)°, β = 100.438(3)°, γ = 102.437(3)°, (2) [Eu(H₂O)₂(C₂O₄)]₂(dipic) · 3H₂O a = 8.2170(6) ?, b = 10.5900(8) ?, c = 13.0670(3) ?, α = 93.951(3)°, β = 103.393(5)°, γ = 107.797(6)°, and (3) [Ce₃(dipic)₃(Hdipic)(SO₄)(H₂O)₃] · 4H₂O a = 11.655(1) ?, b = 12.886(1) ?, c = 16.139(2) ?, α = 106.369(8)°, β = 92.90(1)°, γ = 115.787(7)°. They differ by their dimensionality mono-dimensional for (1), tri-dimensional for (2) and bi-dimensional for (3).     

Crystal and Molecular Structures of C6H5CH2SOCH2CONHCH2C6H5 and C6H5SOCH2CON(iC3H7)2

Abstract  The crystal structures for two of the ligands C₆H₅CH₂SOCH₂CONHCH₂C₆H₅ (1) and C₆H₅SOCH₂CON(ⁱC₃H₇)₂ (2) have been determined by X-ray diffraction. These compounds crystallize in orthorhombic system with space groups and cell parameters, Pca21(no. 29), a = 8.4600(5) ?, b = 5.3534(5) ?, c = 32.136(2) ?, V = 1455.42(15) ?³ and Pna21(no. 33) a = 17.5563(11) ?, b = 5.7902(4) ?, c = 14.2866(9) ?, V = 1452.30(16) ?³, respectively. These molecules are stabilized in solid state by various intra and intermolecular hydrogen bonding interactions to give polymeric structures. The reported IR spectra of these compounds in solid state could be explained on the basis of the observed intermolecular hydrogen bonding interactions. Index Abstract  The title compounds C₆H₅CH₂SOCH₂CONHCH₂C₆H₅ (1) and C₆H₅SOCH₂CON(ⁱC₃H₇)₂ (2) were prepared by the oxidation of corresponding sulfides with H₂O₂/SeO₂ in methanol and their structures were determined. The structures show that the SO and CO groups are having “anti” configuration in 1 and “syn” configuration in 2. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Structural Studies of the Coupling Products Between (C6H5)CH=NR (R?=?C6H5, i-C3H7) and the Ti(C5H5)(2,4-C7H11) Fragment (C7H11?=?dimethylpentadienyl)

Abstract  

The reactions of imines of the formula (C₆H₅)CH=NR (R = C₆H₅, i-C₃H₇) with Ti(C₅H₅)(2,4-C₇H₁₁)(PMe₃) (C₇H₁₁ = dimethylpentadienyl) lead to expulsion of the PMe₃ and coupling between the imine’s carbon atom and a single terminus of the 2,4-C₇H₁₁ ligand, resulting in C₅H₅, “diene,” and π-amide coordination in the 16 electron products. Examination of the Ti–C and C–C bonding parameters for the “diene” ligands reveals that they may be more appropriately regarded as enediyl ligands, leading to a formal +4 oxidation state for titanium. Both complexes crystallize in the triclinic space group P[`1] P\overline{1} . For the R = C₆H₅ coupling product, a = 10.4590(2) ?, b = 11.6407(2) ?, c = 17.3729(3) ?, α = 74.7610(7)°, β = 79.8600(6)°, γ = 82.2895(11)°, V = 2000.28(6) ?³, D _calc = 1.293 g/cm³ at 150(1) K. For the R = i-C₃H₇ coupling product, a = 8.1039(2) ?, b = 9.4115(2) ?, c = 13.0116(4) ?, α = 88.9906(18)°, β = 73.2780(15)°, γ = 83.3088(16)°, V = 943.82(4) ?³, D _calc = 1.250 g/cm³ at 150(1) K.     

Synthesis,Crystal Structure and IR Spectra of Complexes of Mn(II) by Indole-2-Carboxylic or Isoquinoline-1-Carboxylic Acids and 1,10-Phenanthroline

Abstract  

Two ternary complexes of manganese(II) indole-2-carboxylate (2-IC⁻) or isoquinolinecarboxylate (IQC⁻) with 1,10-phenanthroline (phen) in methanol or in dimethylacetamide (DMA) were synthesized and studied by X-ray diffraction and IR spectra. [Mn(C₉H₆NO₂)₂(C₁₂H₈N₂)₂]·CH₄O (1) crystallizes in the triclinic space group P-1 with cell parameters of a = 10.548(2) ?, b = 14.168(3) ?, c = 14.580(3) ?, α = 62.35(2)°, β = 69.16(2)°, γ = 78.61(2)°, V = 1802.4(6) ?³ and Z = 2; [Mn(C₁₀H₆NO₂)₂(C₁₂H₈N₂)].C₄H₉NO (2) crystallizes in the monoclinic space group P2₁/a with cell parameters of a = 15.304(5) ?, b = 12.871(5) ?, c = 17.421(5) ?, β = 114.39(1), V = 3125(2) ?³ and Z = 4. In 1, Mn is six-coordinate by two bidentate phen ligands and two 2-IC⁻ ligands and exhibits a very distorted octahedral geometry. This complex is solvated by methanol involved in hydrogen bonding. In 2, Mn atom is surrounded by one bidentate phen ligand and two bidentate IQC⁻ ligands. The complex exhibits a distorted octahedral geometry around the Mn^II atom. The crystal structure is completed by a disordered DMA solvate molecule. The IR spectra of both compounds are slightly different in the range 4000–2400 cm⁻¹ which may be attributed to hydrogen bond lack in 2.     

A new one-dimensional oxalato- and acetato-bridged Mn(II) polymer with 1,10-phenanthroline as terminal ligand: [Mn2(C12N2H8)2(μ-C2O4)(μ-CH3COO)2] n ·4nH2O

A new oxalato- and acetato-bridged Mn(II) polymer, [Mn₂(C₁₂N₂H₈)₂(μ-C₂O₄)(μ-CH₃COO)₂] _n ·4nH₂O was synthesized and characterized by X-ray diffraction analysis. The compound exhibits a one-dimensional chain-like structure, in which the Mn atom is coordinated by two nitrogen atoms and four carboxyl oxygen atoms with octahedral coordination geometry. As far as we are aware, this type of coordination polymer involving the simultaneously bridging oxalate and acetate ligands has not been studied so far.     

On the Two Closely Related Phases of [Ru(C5Me5)(η6-1,3-(Me2NCH2)2C6H4)](BF4) and the Reversible Solid–Solid Order–Disorder Phase Transition

Abstract  

Crystals of the complex [Ru(C₅Me₅)(η⁶-1,3-(Me₂NCH₂)₂C₆H₄)](BF₄) have been examined over the temperature range 150–300 K via X-ray diffraction measurements. This study shows that the Ru complex is a two-phase system in this T-range and the solid–solid transition is reversible. At 150 K, phase II (P2₁/c, Z′ = 4) is ordered and non-merohedrally twinned, a = 16.4396 (9) ?, b = 17.3226 (4) ?, c = 32.1874 (11) ?, β = 91.375 (2)°. At 295 K, phase I (Pbca, Z′ = 1) is disordered, a = 8.5071 (3) ?, b = 17.1567 (3) ?, c = 32.8250 (8) ?. The relationship between the two phases is obvious because the packing remains similar in the two phases. The greatest structural changes between the two phases are found in the rows of adjacent cations [Ru(C₅Me₅)(η⁶-1,3-(Me₂NCH₂)₂C₆H₄)]⁺ packed along the a direction. These rows are ordered in phase II but are disordered in phase I. The phase transition is first order. Significant changes in thermal motion for the cations are considered as being the driving force for the occurrence of this phase transition.     

Decarbonylation Reaction of [Os3(CO)10(μ-H)(μ-SN2C4H5)]: X-ray Structures of the Two Isomers of [Os3(CO)9(μ-H)(μ 3-η 2-SN2C4H5)]

Abstract  The thermal reaction of [Os₃(CO)₁₀(μ-H)(μ-SN₂C₄H₅)] (1) at 110 °C afforded the new compound [Os₃(CO)₉(μ-H)(μ ₃-η ²-SN₂C₄H₅)] (2) in 84% yield. Compound 2 exists as two isomers, which differ in the disposition of the bridging hydride ligand. Both of the isomers of 2 have been characterized by a combination of elemental analysis, infrared and ¹H NMR spectroscopic data together with single crystal X-ray crystallography. The isomers crystallize together in the triclinic space group P-1 with a = 10.4775(2), b = 13.3056(3), c = 15.0325(3) ?, α = 110.8890(10), β = 99.3880(10), γ = 96.1620(10)°, Z = 2 and V = 1900.31(7) ?³. Index Abstract  The synthesis and the molecular structures of the two isomers of [Os₃(CO)₉(μ-H)(μ ₃-η ²-SN₂C₄H₅)] are described. The isomers differ in the disposition of the hydride ligand.      

The Structure and Fluorescence Property of a 3D Supramolecular Network [Cd2(2-mBIM)2Cl2(C4H4O4)(H2O)2(H2O)]n

Abstract  

A cadmium(II) coordination polymer [Cd₂(2-mBIM)₂Cl₂(C₄H₄O₄)(H₂O)₂(H₂O)] _n (1) (wherein 2-mBIM = bis(2-methylimidazo-1-yl) methane, C₄H₄O₄ = succinate anion) has been synthesized and characterized by X-ray diffraction. Complex 1 crystallizes in the monoclinic space group C2/c with a = 23.5265(15) ?, b = 7.3558(5) ?, c = 17.4771(11) ?, β = 90.3560(10)°, V = 3024.5(3) ?³, Z = 4. Each Cd(II) atom is octahedrally coordinated and connected with two adjacent Cd(II) atoms by two individual 2-mBIM ligands in a trans-configuration to form one-dimensional (1D) helical structure. Such 1D helical chain structures were connected to each other via the succinate anion ligands and result in the formation of a two-dimensional (2D) framework. Meanwhile, an overall three-dimensional (3D) supramolecular network was formed via the weak hydrogen bond interactions between metal-coordination and free water molecules.     

Crystal Structure of [Me2NCH(O)]2Mg[(μ-OPri)2Al(OPri)2]2

Abstract  

Magnesium aluminum isopropoxide coordinates two solvent molecules when crystallized from dimethylformamide yielding the title compound, [Me₂NCH(O)]₂Mg[(μ-OPr ⁱ )₂Al(OPr ⁱ )₂]₂, a potential CVD and sol–gel precursor of spinel, MgAl₂O₄: monoclinic, P2₁/c, a = 18.876(3) ?, b = 12.5225(19) ?, c = 18.578(3) ?, β = 108.333(2)°, V = 4168.6(11) ?³, Z = 4, Mg[(μ-OPr ⁱ )₂Al(OPr ⁱ )₂]₂.     

Synthesis and Crystal Structure Determination of Methyl 2-acetyl-5′-phenyl-2H-spiro[benzo[d]isothiazole-3,3′-pyrazole]-1,1-dioxide-2′(4′H)-carboxylate and Methyl 2-acetyl-5′-(2-thienyl)-2H-spiro[benzo[d]isothiazole-3,3′-pyrazole]-1,1-dioxide-2′(4′H)-carboxylate

Abstract  

Dilithiated C(α), N-carbomethoxyhydrazones were condensed with lithiated methyl 2-(aminosulfonyl)benzoate to afford intermediates that were isolated and not characterized but cyclized with acetic anhydride, which also resulted in N-acetylation. The X-ray crystal structure determinations of methyl 2-acetyl-5′-phenyl-2H-spiro[benzo[d]isothiazole-3,3′-pyrazole]-1,1-dioxide-2′(4′H)-carboxylate and methyl 2-acetyl-5′-(2-thienyl)-2H-spiro[benzo[d]isothiazole-3,3′-pyrazole]-1,1-dioxide-2′(4′H)-carboxylate products were a follow up for absorption spectra, and they confirmed their structures. Mechanistic intermediates to describe the reaction may include C-acylated intermediates that cyclize to spiro(N-benzoisothiazole dioxide-pyrazole) instead of N-carbomethoxypyrazole-ortho-benzenesulfonamides. Crystals of C₁₉H₁₇N₃O₅S 7 are monoclinic, P2₁/c, a = 11.899(2) ?, b = 17.562(4) ?, c = 9.484(2) ?, β = 111.03(3)°, Z = 4, V = 1849.9(6) ?³, R ₁ = 0.0857 and wR ₂ = 0.2216 for reflections with I > 2σ(I); crystals of C₁₇H₁₅N₃O₅S₂ 8 are orthorhombic, Pbca, a = 16.045(3) ?, b = 10.746(2) ?, c = 20.389(4) ?, Z = 8, V = 3516(1) ?³, R ₁ = 0.0841 and wR ₂ = 0.2179 for all reflections with I > 2σ(I).     

Preparation and Characterization of Bis(μ-1,2-diaminoethane)cobalt(II) Hexavanadate: A Layered Polyoxovanadate Pillared by a Cobalt Coordination Complex

Abstract  The first example of polyoxovanadate layered framework with a cobalt coordination complex as a pillaring unit, Co^II(μ-C₂N₂H₈)₂[V₄^IVV₂^VO₁₄], was readily synthesized under hydrothermal conditions. The structure can be solved and refined in monoclinic P2 ₁ /n with a = 9.143(3) ?, b = 6.5034(11) ?, c = 15.874(4) ?, β = 101.90(2), V = 923.6(4) ?³ and Z = 2. The crystal structure comprises two-dimensional {V₄^IVV₂^VO₁₄}²⁻ layers extending parallel to [101], constructed from tetrahedral {V^VO₄} and square pyramidal {V^IVO₅} building units. Adjacent layers are linked through the octahedral {Co^IIO₂(μ-C₂N₂H₈)₂} pillars, within which the Co^II resides on an inversion center. The structure displays N–H···O and C–H···O hydrogen bonding between the ethylenediamine and vanadium oxide layers. Graphical Abstract  A new polyoxovanadate layered framework pillared with a cobalt coordination complex, Co^II(μ-C₂N₂H₈)₂[V₄^IVV₂^VO₁₄], has been prepared hydrothermally and fully characterized.      

Synthesis,Structure and Reactivity of Electron Deficient Triosmium Cluster Bearing 2,6-Dimethylbenzothiazolide Ligand

Abstract  

Reaction of [Os₃(CO)₁₀(NCMe)₂] with 2,6-dimethylbenzothiazole at room temperature affords [Os₃(CO)₁₀(μ-H){μ-η ²-C₇H₂NS(Me)₂}] (1) in 45% yield. Decarbonylation of 1 in refluxing toluene furnishes the electron-deficient cluster [Os₃(CO)₉(μ-H){μ ₃-η ²-C₇H₂NS(Me)₂}] (2) in almost quantitative yield. Treatment of 2 with PPh₃ at 40 °C gives the addition product [Os₃(CO)₉(PPh₃)(μ-H){μ-η ²-C₇H₂NS(Me)₂}] (3) in 85% in which the PPh₃ ligand is coordinated to the rear osmium atom. A similar treatment of 2 with P(OMe)₃ gives [Os₃(CO)₉{P(OMe)₃}(μ-H){μ-η ²-C₇H₂NS(Me)₂}] (4) in 60% yield with P(OMe)₃ ligand also coordinated to the rear metal. Compounds 3 and 4 differ by the disposition of the hydride ligands. In compound 4 both the hydride and the heterocyclic ligands simultaneously bridge the same metal–metal edge whereas they bridge different metal–metal edges in 3. Compounds 1–4 have been characterized by a combination of elemental analysis, infrared, NMR and mass spectral data together with single crystal X-ray diffraction studies for 3. Compound 3 crystallizes in the monoclinic space group P2₁/n with a = 9.2659(10), b = 23.643(2), c = 16.382(3) Å, β = 91.324(12)°, Z = 4 and V = 3,587.8(8) Å³.     

Crystal Structure,Thermal Analysis and IR Spectroscopic Investigation of Bis Benzyl Ammonium Monohydrogentetraoxoarsenate(V) Monohydrate

Abstract  

The salt bis benzyl ammonium monohydrogentetraoxoarsenate(V) monohydrate [C₆H₅CH₂NH₃ ⁺]₂HAsO₄ ²⁻·H₂O, M = 373.92, Triclinic, P−1. a = 6.514(1), b = 8.910(2), c = 15.061(3) ?, α = 99.26(2), β = 93.93(1), γ = 97.64(1)°, V = 851.5(3), Z = 2, D _x  = 1.460, λ (MoKα) = 0.71073 ?, μ = 0.99 mm⁻¹, F(000) = 126, T = 20(2)  °C, final R = 0.673 for 5488 unique reflections. Planes of HAsO₄ ²⁻ alternate with planes of C₆H₅CH₂NH₃ ⁺ groups. The structure consists of infinite parallel two-dimensional planes built of mutually connected ions and water molecules by strong O–H···O and N–H···O hydrogen bonding. There are no contacts other than van der Waals interactions between the layers. Differential scanning calorimetry study on bis benzyl ammonium monohydrogentetraoxoarsenate(V) monohydrate was carried out. The infrared of polycrystalline samples of this compound have been recorded at room temperature.     

Synthesis and Structural Characterization of Two New Layered Inorganic–Organic Hybrid Zinc Phosphites Templated by Cyclam: Zn(HPO3)2·0.5(C10H28N4) and Zn2(HPO3)3·0.5(C10H28N4)

Abstract  

Using 1,4,8,11-tetraazacyclotetradecane (cyclam) as a template, two new layered zincophosphites, Zn(HPO₃)₂·0.5(C₁₀H₂₈N₄) (1) and Zn₂(HPO₃)₃·0.5(C₁₀H₂₈N₄) (2), were synthesized and characterized by single crystal X-ray diffraction. The two new compounds crystallize in the triclinic system with the space group P − 1 and the cell parameters: a = 8.3130 ?, b = 8.7289 ?, c = 9.0055 ?, α = 106.90(1), β = 95.56(1), γ = 105.30(1), V = 592.31 ?³, Z = 2 for 1 and a = 9.0406 ?, b = 9.4234 ?, c = 9.4519 ?, α = 91.19(1), β = 100.73(1), γ = 106.85(1), V = 754.82 ?³, Z = 2 for 2. Both structures are described in terms of phosphometallic slabs hosting the cyclam cation.     

Investigations of 2-Thiazoline-2-thiol as a Ligand: Synthesis and X-ray Structures of [Mn2(CO)7(μ-NS2C3H4)2] and [Mn(CO)3(PPh3)(κ2-NS2C3H4)]

Abstract  Treatment of Mn₂(CO)₁₀ with 2-thiazoline-2-thiol in the presence of Me₃NO at room temperature afforded the dimanganese complexes [Mn₂(CO)₇(μ-NS₂C₃H₄)₂] (1) and [Mn₂(CO)₆(μ-NS₂C₃H₄)₂] (2) in 51 and 34% yields, respectively. Compound 1 was quantitatively converted into 2 when reacted with one equiv of Me₃NO. Reaction of 1 with triphenylphosphine at room temperature furnished the mononuclear complex [Mn(CO)₃(PPh₃)(κ ²-NS₂C₃H₄)] (3) in 66% yield. All three new complexes have been characterized by elemental analyzes and spectroscopic data together with single crystal X-ray diffraction studies for 1 and 3. Compound 1 crystallizes in the orthorhombic space group Pbca with a = 12.4147(2), b = 16.2416(3), c = 19.0841(4) ?, β = 90°, Z = 8 and V = 3848.01(12) ?³ and 3 crystallizes in the monoclinic space group P 2₁/n with a = 10.41730(10), b = 14.7710(2), c = 14.9209(2) ?, β = 91.1760(10)°, Z = 4 and V = 2295.45(5) ?³. Graphical Abstract  Two new dimanganese complexes [Mn₂(CO)₇(μ-NS₂C₃H₄)₂] (1) and [Mn₂(CO)₆(μ-NS₂C₃H₄)₂] (2) were formed when [Mn₂(CO)₁₀] was treated with 2-thiazoline-2-thiol in the presence of Me₃NO. Compound 2 reacts with PPh₃ to give the monomeric complex [Mn(CO)₃(PPh₃ )(κ ²-NS₂C₃H₄)]. The structures of 1 and 3 were established by crystallography. Shishir Ghosh, Faruque Ahmed, Rafique Al-Mamun, Daniel T. Haworth, Sergey V. Lindeman, Tasneem A. Siddiquee, Dennis W. Bennett, Shariff E. Kabir Investigations of 2-thiazoline-2-thiol as a ligand: Synthesis and X-ray structures of [Mn₂(CO)₇(μ-NS₂C₃H₄)₂] and [Mn(CO)₃ (PPh3)(κ ²-NS₂C₃H₄)].      

Synthesis and Crystal Structures of a Pair of Isostructural Azido-Bridged Polynuclear Schiff Base Zinc(II) Complexes

Abstract  

A pair of novel isostructural azido-bridged polynuclear zinc(II) complexes, [Zn₂(L1)₂(μ_1,1-N₃)(μ_1,3-N₃)] _n (1) and [Zn₂(L2)₂(μ_1,1-N₃)(μ_1,3-N₃)] _n (2) (HL1 = 2-bromo-4-chloro-6-[(2-isopropylaminoethylimino)methyl]phenol, HL2 = 2,4-dibromo-6-[(2-isopropylaminoethylimino)methyl]phenol), have been synthesized and structurally characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. Both complexes crystallize in the orthorhombic space group Pcca. Crystal data for (1): a = 22.567(4) ?, b = 8.414(2) ?, c = 17.268(3) ?, V = 3279.0(11) ?³, Z = 8, R ₁ = 0.0441, and wR ₂ = 0.0846. Crystal data for (2): a = 22.536(4) ?, b = 8.409(2) ?, c = 17.531(3) ?, V = 3322.2(11) ?³, Z = 8, R ₁ = 0.0538, and wR ₂ = 0.0906. X-ray structure determination revealed that each zinc(II) atom in the complexes is in a trigonal–bipyramidal coordination, with one imine N atom of a Schiff base ligand and two N atoms from two bridging azide ligands defining the basal plane, and one phenolate O and one amine N atoms of the Schiff base ligand occupying the two axial positions.     

Reactivity of [Re2(CO)8(MeCN)2] With 1-vinylimidazole: X-ray Structures of [Re2(CO)8{η1-NC3H3N(CH=CH2)}2] and [ReCl2(CO)2{η1-NC3H3N(CH=CH2)}2]

Abstract  Treatment of [Re₂(CO)₈(MeCN)₂] with excess 1-vinylimidazole in refluxing benzene gives three new compounds [Re₂(CO)₉{η ¹-NC₃H₃N(CH=CH₂)}] (1), [Re₂(CO)₈{η ¹-NC₃H₃N(CH=CH₂)}₂] (2) and [ReCl₂(CO)₂{η ¹-NC₃H₃N(CH=CH₂)}₂] (3) in 11, 32 and 2% yields, respectively. The solid-state structures of complexes 2 and 3 have been determined by single crystal X-ray diffraction studies. Compound 2 crystallizes in the monoclinic space group C2/c, with lattice parameters a = 13.8378(5) ?, b = 11.8909(5) ?, c = 14.4591(6) ?, β = 116.6470(10)°, Z = 4 and V = 2131.99(15) ?³. Compound 3 crystallizes in the monoclinic space group C2/c, with lattice parameters a = 10.1028(3) ?, b = 13.5640(5) ?, c = 12.5398(4) ?, β = 109.637(2)°, Z = 4 and V = 1618.4(9) ?³. The disubstituted dinuclear compound 2 contains two 1-vinylimidazole ligands coordinated through the imino nitrogen atoms at the equatorial sites, whereas the mononuclear compound 3 contains two carbonyl ligands, two N coordinated η ¹-1-vinylimidazole ligands and two terminal Cl ligands. Graphical Abstract  Two dinuclear complesxes [Re₂(CO)₉{η ¹-NC₃H₃N(CH=CH₂)}] (1) and [Re₂(CO)₈{η ¹-NC₃H₃N(CH=CH₂)}₂] (2) and the mononuclear [ReCl₂(CO)₂{η ¹-NC₃H₃N(CH=CH₂)}₂] (3) were obtained from the reaction of [Re₂(CO)₈(MeCN)₂] with excess 1-vinylimidazole at 80 °C. The X-ray structrures of 2 and 3 are described.      

Structural Modulation in Lanthanide Tetracyanoplatinates Incorporating Terpyridine: Synthesis and Structures of Four Distinct One-Dimensional Variants

Abstract  

The synthesis of four different lanthanide tetracyanoplatinates all incorporating 2,2′:6′,2″-terpyridine have been carried out in acetonitrile/water mixtures by reaction of an appropriate Ln³⁺ salt with 2,2′:6′,2″-terpyridine and potassium tetracyanoplatinate. The use of different Ln³⁺ salts as reactants results in the isolation of {La(tpy)(H₂O)₃}₂[Pt(CN)₄]₃·2CH₃CN·2H₂O (La-1) space group P[`1] P\bar{1} , a = 9.3862(15) ?, b = 12.186(1) ?, c = 13.493(1) ?, α = 88.082(7)°, β = 80.22(1)°, γ = 74.88(1)°, {Pr(tpy)(H<sub>2</sub>O)<sub>3</sub>}<sub>2</sub>[Pt(CN)<sub>4</sub>]<sub>3</sub>·2H<sub>2</sub>O (Pr-2) space group P[`1] P\bar{1} , a = 9.2458(15) ?, b = 10.8068(9) ?, c = 13.6178(14) ?, α = 84.554(8)°, β = 74.905(10)°, γ = 79.490(9)°, Ho(tpy)(H₂O)₂(NO₃)[Pt(CN)₄] · CH₃CN (Ho-3) space group P2₁/c, a = 12.867(1) ?, b = 15.1046(15) ?, c = 13.651(4) ?, β = 105.39(1)°, or Yb(tpy)(H₂O)₂(NO₃)[Pt(CN)₄]·0.5CH₃CN·1.5H₂O (Yb-4) space group Pbcn, a = 13.226(7) ?, b = 15.870(2) ?, c = 24.276(3) ? under quite similar reaction conditions. All four of these compounds have been isolated as single crystals and X-ray diffraction has been used to investigate their structural features. None of these compounds are isostructural with one another, but all contain one-dimensional, polymeric structures that contain tris chelation of the Ln³⁺ cations by terpyridine and bridging of the Ln³⁺ ions by tetracyanoplatinate. La-1 and Pr-2 contain both cis- and trans-bridging of Ln³⁺ cations by tetracyanoplatinate resulting in double chains with a ladder-type structure. Ho-3 and Yb-4 are similar in that they contain chelation of Ln³⁺ by both terpyridine and a nitrate anion and both structure types only contain cis-bridging by tetracyanoplatinate. All four structures contain Pt–Pt interactions in the form of dimeric units.     

Diphosphine ligand substitution in H4Ru4(CO)12: X-ray diffraction structures and reactivity studies of the cluster compounds H4Ru4(CO)10(P–P) [where P–P–(Z)–Ph2PCH–CHPPh2, bpcd]

The tetraruthenium cluster H₄Ru₄(CO)₁₂ (1) has been studied for its reactivity with the unsaturated diphosphine ligands (Z)–Ph₂PCH–CHPPh₂ and 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) under thermal, near-UV photolysis, and Me₃NO-assisted activation. All three cluster activation methods promote loss of CO and furnish the anticipated substitution products H₄Ru₄(CO)₁₀[(Z)–Ph₂PCH–CHPPh₂] (2) and H₄Ru₄(CO)₁₀(bpcd) (3) that possess a chelating diphosphine ligand. Clusters 2 and 3 have been characterized in solution by IR and NMR spectroscopies, and these data are discussed with respect to the crystallographically determined structure for both new cluster compounds. The ³¹P NMR spectral data and the solid-state structures confirm the presence of a chelating diphosphine ligand in clusters 2 and 3. Cluster 2 crystallizes in the monoclinic space P2₁/c, a=11.768(6) ?, b=18.521(9) ?, c=20.48(1) ?, β=102.291(8)°, V=4361(4) A³, Z=4, and d _calc=1.726 Mg/m³; R=0.0225, R _w=0.0491 for 6798 reflections with I > 2σ(I). The four bridging hydrides were located in H₄Ru₄(CO)₁₀[(Z)–Ph₂PCH–CHPPh₂] and their adopted positions are discussed relative to the solution ¹H NMR spectrum. H₄Ru₄(CO)₁₀(bpcd) crystallizes in the orthorhombic space Pbca, a=19.072(3) ?, b=20.169(3) ?, c=22.774(3) ?, V=8760(2) A³, Z=8, and d _calc=1.870 Mg/m³; R=0.0428, R _w=0.0896 for 10296 reflections with I > 2σ(I). Sealed NMR tubes containing clusters 2 and 3 were found to be exceeding stable towards near-UV light and temperatures up to ca. 125 °C. The surprisingly robust behavior of 2 and 3 is contrasted with the related cluster Ru₃(CO)₁₀(bpcd) that undergoes fragmentation to the donor-acceptor compound Ru₂(CO)₆(bpcd) and the phosphido-bridged compound Ru₂(CO)₆(μ–PPh₂)[μ–C–C(PPh₂)C(O)CH₂C(O)] under mild conditions. The electrochemical properties of each substituted cluster have been investigated by cyclic voltammetry, and our findings are discussed with respect to the reported electrochemical data on the parent cluster H₄Ru₄(CO)₁₂.