Structural investigation of salts containing ions [Pd(NH<Subscript>3</Subscript>)<Subscript>4</Subscript>]<Superscript>2+</Superscript> and [IrF<Subscript>6</Subscript>]<Superscript>2–</Superscript>

Double complex salts (DCS) α-[Pd(NH₃)₄][IrF₆]·H₂O (P2₁/m, a = 6.3181(3) Å, b = 10.8718(5) Å, с = 7.4526(4) Å, β = 103.568(2)°), β-[Pd(NH₃)₄][IrF₆]·H₂O (P2₁/с, a = 8.5773(3) Å, b = 10.8791(4) Å, с = = 12.6741(3) Å, β = 122.497(2)°), [Pd(NH₃)₄]₃[IrF₆]₂Cl₂·H₂O (P-1, a = 7.6080(2) Å, b = 7.6274(2) Å, с = 11.8070(3) Å, β = 122.497(2)°), and [Pd(NH₃)₄]₂[IrF₆]NO₃ (Fm-3m, a = 11.21210(10) Å) have been synthesized and structurally characterized for the first time. The existence of polymorphs for the DCS has been revealed. The influence of the chemical composition of the initial reagents on the reaction course and, respectively, the products, has been demonstrated. A hypothesis on the influence of the second coordination sphere on the formation of one or the other polymorph of the DCS has been suggested. It has been shown that the series α-[Pd(NH₃)₄][МF₆]·H₂O (M = Pt, Pd) exhibits isostructurality.     

Photochemical arene exchange in the naphthalene complex [CpRu(η<Superscript>6</Superscript>-C <Subscript>10</Subscript>H<Subscript>8</Subscript>)]<Superscript>+</Superscript>

The cation [CpRu(η⁶-C₁₀H₈)]⁺ was shown to exchange naphthalene for other arenes under visible-light irradiation to form the complexes [CpRu (η⁶-arene)]⁺ (arene = C₆H₆, 1,4-C₆H₄Me₂, 1,3,5-C₆H₃Me₃, or 1,2,4,5-C ₆H₂Me₄) in 70–95% yields. The reaction rate of exchange decreases in the series arene = 1,4-C₆H₄Me₂ > C₆H₆ > 1,3,5-C₆H₃Me₃ > 1,2,4,5-C ₆H₂Me₄ >> C₆Me₆ and increases with the coordinating ability of the solvent in the order CH₂Cl₂ < THF—CH₂Cl₂ mixture (1: 1) < acetone.     

Thermal arene exchange in the naphthalene complex [CpRu(η<Superscript>6</Superscript>-C<Subscript>10</Subscript>H<Subscript>8</Subscript>)]<Superscript>+</Superscript>

Naphthalene in the [CpRu(⁶−C₁₀H₈)]⁺ complex (1) is substituted for other arenes under reflux in 1,2-dichloroethane to form the [CpRu(⁶-arene)]⁺ cations (arene = C₆H₆, 1,2-C₆H₄Me₂, 1,2,4,5-C₆H₂Me₄, or C₆Me₆) in 70–80% yields. The reaction is accelerated in the presence of a catalytic amount of acetonitrile. The structure of [1]PF₆ was established by X-ray diffraction.     

Structure of sulfanilamide-containing cobalt(III) dioximates with the [ZrF<Subscript>6</Subscript>]<Superscript>2−</Superscript> and [BF<Subscript>4</Subscript>]<Superscript>−</Superscript> anions

The complexes [Co(DH)₂(Sam)₂]₂[ZrF₆]·5H₂O (I) and [Co(DH)₂(Sam)₂][BF₄]·H₂O (II), where DH^? is the dimethylglyoxime monoanion, and Sam is para-aminobenzenesulfamide (sulfanilamide, white streptocid), were synthesized, and their crystal structures were determined by X-ray diffraction analysis. The coordination polyhedron of the Co³⁺ atom is an N₆ octahedron formed by four nitrogen atoms of the two dimethylglyoxime residues and two nitrogen atoms of the Sam fragments. The latter are realized in virtually parallel orientation relative to the polyhedron of the metal atom and its equatorial plane; the average value of the dihedral angles is 26.8(1)°, and there is π-π interaction between the benzene rings of the Sam fragments and the π delocalized equatorial metallocycle. The deviation of the cobalt atom from the four-angle plane is up to 0.009(1) Å. The (Co-N)_DH? and (Co-N)_Sam distances in the [Co(DH)₂(Sam)₂]⁺ complex cations vary from 1.892(2) Å to 1.907(3) Å and from 2.000(2) Å to 2.012(2) Å, respectively. The [ZrF₆]^2? and [BF₄]^? complex anions play the major role in crystal formation; they produce a substantial effect on the formation of a complex system of hydrogen bonds.     

Interaction of [В<Subscript>10</Subscript>H<Subscript>10</Subscript>]<Superscript>2–</Superscript> and [В<Subscript>12</Subscript>H<Subscript>12</Subscript>]<Superscript>2–</Superscript> with nitro compounds

The interaction of the [B₁₀H₁₀]^2– and [B₁₂H₁₂]^2– anions with aliphatic and aromatic nitro compounds (RNO₂, where R = Et, n-Pr, i-Pr, tert-Bu, Ph) has been studied under irradiation with visible and UV light. It has been shown that, depending on the reaction conditions, both mono- and disubstituted nitro-closo-decaborates can be selectively obtained in yields up to 50%.     

Synthesis and structure of novel coordination compounds based on [Re<Subscript>6</Subscript>Q<Subscript>8</Subscript>(CN)<Subscript>6</Subscript>]<Superscript>4–</Superscript> (Q = S,Se) and (SnMe<Subscript>3</Subscript>)<Superscript>+</Superscript>

The reactions of SnMe₃Cl with salts of the cluster anionic complexes [Re₆Q₈(CN)₆]^4? (Q = S, Se) gave novel complexes [{(SnMe₃)₂(OH)}₂{SnMe₃}₂{Re₆S₈(CN)₆}] (I), (Me₄N)₂[{SnMe₃(H₂O)}₂{Re₆Se₈(CN)₆}] (II), [{(SnMe₂)₄(μ₃-O)}₂{Re₆Se₈(CN)₆}] (III), and [(SnMe₂)₄(μ₃-O)₂(μ₂-OH)₂(H₂O)₂][{SnMe_{3 2}{Re₆Se₈(CN)₆}] (IV). The structures of I–IV were determined by X-ray diffraction. Compounds I, IV have the chain structures with the CN-SnMe₃-NC bridges between the cluster anions [Re₆Q₈(CN)₆]^4?. Compound II contains isolated fragments {SnMe₃(H₂O)}₂{Re₆Se₈(CN)₆}^2?. In the polymer framework of compound III, the cluster anionic complexes [Re₆Se₈(CN)₆]^4? are bound by the complex cations [(SnMe₂)₄(μ₃-O)₂]⁴⁺ formed due to the hydrolysis of the initial (SnMe₃)Cl.     

Framework coordination polymer based on the [Re<Subscript>3</Subscript>Mo<Subscript>3</Subscript>S<Subscript>8</Subscript>(CN)<Subscript>6</Subscript>]<Superscript>6–</Superscript>heterometallic cluster anions and Cd<Superscript>2+</Superscript> cations

A new coordination polymer, [Cd(NH₃)₄]₂{Cd[Re₃Mo₃S₈(CN)₆]}·1.5H₂O (I), was prepared by the reaction between solutions of Cd(CH₃COO)₂ · 2H₂O in aqueous ammonia and CaK₄[Re₃Mo₃S₈(CN)₆] · 8H₂O in water. The crystals are cubic, space group Fm3m (Prussian blue structural type); a = 15.0268(4) Å (CIF file CSD no. 431555). According to ESR data, compound I is paramagnetic, g-factor is 2.298. Thermal stability investigation by TGA and powder X-ray diffraction showed that elimination of coordinated NH₃ molecules is accompanied by sample amorphization.     

Structures of the complex ions [CuCl<Subscript>4</Subscript>]<Superscript>2−</Superscript> and [CuCl<Subscript>5</Subscript>]<Superscript>3−</Superscript>

The electronic structures of the complex ions [CuCl₄]^2? and [CuCl₅]^3? were analyzed in terms of the extended angular overlap model (AOM) with consideration to sd and pd mixing. The total antibonding orbital energies of these ions show no anomalies in the transition from a tetrahedron to a planar square [CuCl₄]^2? and from a trigonal bipyramid to a tetragonal pyramid [CuCl₅]^3?. Presumably, the existence of numerous intermediate forms of these complexes is mainly due to the packing effects rather than the electronic factors.     

Bond variations in the complexes [CuCl<Subscript>6</Subscript>]<Superscript>4−</Superscript>

An extended version of the angular overlap model developed from the fourth-order variational perturbation theory was used to explain why sd mixing for [CuCl₆]^4? and other pseudooctahedral complexes [CuL₆]^n? with the split ground state ² E is responsible for strong softening of the vibrational E mode, which results in lengthening and even cleavage of the bonds between the metal atom and the axial ligands.     

Mercury complex [(HOCH<Subscript>2</Subscript>)<Subscript>3</Subscript>CNH<Subscript>3</Subscript>]<Stack><Subscript>2</Subscript><Superscript>+</Superscript></Stack> [HgI<Subscript>4</Subscript>]<Superscript>2−</Superscript>: Synthesis and structure

The complex [(HOCH₂)₃CNH₃] ₂ ⁺ [HgI₄]^2? (I) was synthesized by reacting (trioxymethyl)methylammonium iodide with mercury dioide (2: 1 mol/mol) in acetone. X-ray crystallography shows that the complex consists of two types of crystallographically independent [(HOCH₂)₃CNH₃]⁺ cations and tetrahedral anions [HgI₄]^2? (IHgI, 106.49(2)°–113.99(4)°; Hg-I, 2.7849(8)-2.8105(8) Å. [(HOCH₂)₃CNH₃]⁺ cations are linked via hydrogen bonds O…H-N and O-H…N (O…N, 2.84–2.92 Å) to form polymer chains, which are cross-linked with one another via anions (I…H, 2.81, 2.82 Å).     

Cobalt—Sandwiched lindqvist hexaniobate dimer [Co(III)H<Subscript>5</Subscript>(Nb<Subscript>6</Subscript>O<Subscript>19</Subscript>)<Subscript>2</Subscript>]<Superscript>8− 1</Superscript>

A new polyoxoniobate K₆Na₂[Co_IIIH₅(Nb₆O₁₉)₂] · 26.5H₂O (I) has been synthesized by a diffusion strategy and structurally characterized by IR spectrum, UV spectroscopy, TG analysis, and single crystal X-ray diffraction. Compound I crystallizes in the cubic Pa \(\bar 3\) space group with a = 17.969(8)Å V = 5802.6(4) ų, Z = 4, R ₁ = 0.0383 and wR ₂ = 0.1187. Compound I consists of the Lindqvist hexaniobate dimer [Co_IIIH₅(Nb₆O₁₉)₂]^8? in which the Co³⁺ cations sare andwiched between and face-shared with two Lindqvist-type [Nb₆O₁₉]^8? subunits. In situ UV spectra display that compound I can stably exist in an aqueous solution.     

Peroxide derivatives of heteropoly compounds with Keggin anions [PW<Subscript>12</Subscript>O<Subscript>40</Subscript>]<Superscript>3−</Superscript> and [SiW<Subscript>12</Subscript>O<Subscript>40</Subscript>]<Superscript>4−</Superscript>: Synthesis and structure

Peroxide derivatives of heteropoly compounds with Keggin anions [PW₁₂O₄₀]^3? and [SiW₁₂O₄₀]^4? are isolated in an individual state from concentrated hydrogen peroxide solutions and characterized by physicochemical methods. The structure of Ba₂[SiW₁₂O₄₀] · 4H₂O₂ · 11H₂O (I) is solved by X-ray crystallography. Crystals of compound I (H₃₀Ba₂O₅₉Si₁W₁₂, FW = 3483.21) are monoclinic, space group C2/c, a = 24.981(2) Å, b = 12.2103(11) Å, c = 18.7142(17) Å, β = 122.620(2)^o, V = 4808.0(8) ų, Z = 4. The structure contains Keggin anions [SiW₁₂O₄₀]^4?; all hydrogen peroxide molecules are coordinated to Ba²⁺ cations.     

Synthesis and Structure of the bismuth complex [Ph<Subscript>3</Subscript>PrP]<Stack><Subscript>4</Subscript><Superscript>+</Superscript></Stack>[Bi<Subscript>4</Subscript>I<Subscript>16</Subscript>]<Superscript>4−</Superscript>

The complex [Ph₃P] ₄ ⁺ [Bi₄I₁₆]^4? · 2 Me₂C=O (I) was synthesized by the reaction of triphenyl(propyl)phosphonium iodide with bismuth iodide in acetone. The crystal structure of complex I was determined by X-ray crystallography. It contains, in addition to solvent molecules, two types of crystallographically independent tetrahedral tetraphenyl(propyl)phosphonium cations and tetranuclear anions [Bi₄I₁₆]^4? in a chair conformation with the bismuth atoms being in an octahedral coordination. The Bi-I distances in the anion vary within 2.8768(4)–3.2524(4) Å.     

Photochemical replacement of benzene in the tetramethylcyclopentadienyl complex of iron, [η-C<Subscript>5</Subscript>Me<Subscript>4</Subscript>H)Fe(η-C<Subscript>6</Subscript>H<Subscript>6</Subscript>)]<Superscript>+</Superscript>

Irradiation of the cation [η-C₅Me₄H)Fe(η-C₆H₆)]⁺+ (1) and Bu^tNC with visible light in acetonitrile results in the displacement of the benzene ligand, giving [(η-C₅Me₄H)Fe(Bu^tNC)₃]+ (2). Reactions of complex 1 with P(OR)₃ and dppe in M_eCN yield the complexes [(η-C₅Me₄H)-Fe(M_eCN)P(OR)_{3 2}]+ (R = Me (3) and Et (4)) and [(η-C₅Me₄H)Fe(MeCN)(dppe)]+ (5) containing two Fe—P bonds. The same reactions in CH₂Cl₂ give the tris(phosphite) complexes [(η-C₅Me₄H)FeP(OR)_{3 3}]+ (6, 7). A photochemical reaction of complex 1 with pentaphos-phaferrocene Cp*Fe(η-cyclo-P₅) yields the triple-decker cation [(η-C₅Me₄H)Fe(μ-η:η-cyclo-P₅)FeCp*]+ (8) with a bridging pentaphospholyl ligand. Structures [2]PF₆ and [3]PF₆ were identified by X-ray diffraction.     

First examples of cyano-bridged complexes based on a novel cluster anion [Re<Subscript>12</Subscript>C<Subscript>17</Subscript>(CN)<Subscript>6</Subscript>]<Superscript>6−</Superscript>

Two cyano-bridged compounds of novel dodecanuclear cluster anion [Re₁₂CS₁₇(CN)₆] with Ni²⁺ cations were synthesized, namely, one-dimensional polymer of the composition [{Ni(NH₃)₄} {Ni(NH₃)₅}₂Re₁₂CS₁₇(CN)₆] · 7H₂O (I) with a chain structure and [Ni(NH₃)₆]₃[{Ni(NH₃)₄}₃ {Re₁₂CS₁₇(CN)₆}₂] · 21H₂O (II), containing the anionic dimeric complex [{Ni(NH₃)₄}₃ {Re₁₂CS₁₇(CN)₆}₂]^6?. The structures of both compounds were established by X-ray diffraction analysis. Crystals I are monoclinic, space group P2/n, a = 15.321(3), b = 12.635(2), c = 15.448(3) Å, β = 100.242(3)°, V = 2942.8(8) ų, Z = 2. Crystals II are trigonal, space group R3, a = b = 19.7987(14), c = 28.8642(18) Å, V = 9798.6(12) ų, Z = 3.     

Structural characterization of two lanthanide complexes attached to [H<Subscript>2</Subscript>W<Subscript>12</Subscript>O<Subscript>40</Subscript>]<Superscript>6−</Superscript>

In this article, two compounds [H₂bpy][Ln(DMF)₄(H₂O)₃(Hbpy)][H₂W₁₂O₄₀] (Ln = La,Ce; DMF = N,N-dimethylformamide, bpy = 4,4′-bipyridine) have been synthesized and characterized by single-crystal X-ray diffraction, IR spectra, and TG analysis. X-Ray analysis showed that the [Ln(DMF)₄(H₂O)₃(Hbpy)]⁴⁺ unit is supported on the α-Keggin polyoxoanion [H₂W₁₂O₄₀]⁶⁻ via the surface bridging oxygen atom. The [H₂bpy][Ln(DMF)₄(H₂O)₃(Hbpy)][H₂W₁₂O₄₀] entity is further extended into 2D supramolecular networks with 1-D channels by hydrogen-bonding interactions, in which 4,4′-bipy ligands reside. To the best of our knowledge, these complexes represent the first examples of rare earth metal-organic complex-decorated α-metatungstate clusters. Furthermore, the electrochemical properties of these compounds have been studied via the method of bulk-modified carbon paste electrodes.     

A New Sandwich Polyoxometalate Constructed from a Zn<Stack><Subscript>6</Subscript><Superscript>12+</Superscript></Stack> Hexagon Cluster Sandwiched by Two B-α-[BiW<Subscript>9</Subscript>O<Subscript>33</Subscript>]<Superscript>9−</Superscript>

A new sandwich polyoxometalate Na₄Zn₂[Zn₂(H₂O)₁₀(ZnCl)₆(B-α- BiW₉O₃₃)₂] · 40.5H₂O (1) has been obtained in aqueous solution and characterized by IR, UV, element analysis, TG and single-crystal X-ray analysis. Polyoxoanion 1 is composed of a Zn ₆ ¹²⁺ hexagon sandwiched by two [BiW₉O₃₃]^9? units, which is firstly observed in tungstobismutate. The crystal data for compound 1: Triclinic, space group P–1, a = 15.426(3) Å, b = 15.467(3) Å, c = 15.526(3) Å, α = 74.24(3)°, β = 64.37(3)°, γ = 60.73(3)°, V = 2905.3(1) ų, Z = 1.     

Synthesis of diamantane via skeletal isomerization of hydrogenated cyclohepta-1,3,5-triene dimers in ionic liquid [Et<Subscript>3</Subscript>NH]<Superscript>+</Superscript> [Al<Subscript>2</Subscript>Cl<Subscript>7</Subscript>]<Superscript>–</Superscript>

Diamantane was synthesized in 91–97% yield by skeletal isomerization of a mixture of hydrogenated cyclohepta-1,3,5-triene dimers, pentacyclo[8.4.0.0^3,7.0^4,14.0^6,11]tetradecane and pentacyclo-[7.5.0.0^2,8.0^5,14.0^7,11]tetradecane, at a ratio of 3: 2 in the presence of ionic liquid [Et₃NH]⁺ [Al₂Cl₇]^–.