Crystal structure oftrans-tetrachlorobis[2-(2-1H-imidazolyl)-1H-imidazolium]cadmium(II), [Cd(H3biim)2Cl4]

The reaction between cadmium(II) chloride and 2,2'-bi-1H-imidazole (H₂biim) in an acidic solution affords [Cd(H₃biim)₂Cl₄] (H₃biim=2-(2-1H-imidazolyl)-1H-imidazolium) in 63% yield. The compound crystallizes in the triclinic space groupP1, wherea=8.072(2),b=8.100(2),c=8.593(2) Å, =75.89(2), =62.94(2), =63.29(1)°,V=446.4(2) ų, andZ=1. The central Cd atom exhibits an octahedral geometry composed of a Cl₄N₂ core. The Cd-N bond distance is 2.392(2) Å. Cd–Cl distances are 2.5919(9) and 2.671(1) Å.     

Helical chirality of pyrrolo[1,2-a][1,10]phenanthroline derivatives

The objective of the study was to confirm by X-ray analysis the phenomenon of helical chirality inferred from solution ¹H-NMR data for a series of derivatives based on the novel pyrrolo[1,2-a][1,10]phenanthroline system. The syntheses of the title compounds and their ¹H-NMR data are presented. Crystals of the representative compound ethyl, 1-(4-phenylbenzoyl)-pyrrolo[1,2-a][1,10]phenanthroline-3-carboxylate, with molecular formula C₃₁H₂₂N₂O₃, were found to crystallize in the triclinic system, space group P 1 with a = 7.8541(1), b = 11.2605(2), c = 13.4093(3) Å, = 92.244(1), = 90.292(1), = 106.475(1) and Z = 2. The X-ray analysis revealed the predicted helicity of the phenanthroline system as well as its origin, namely the proximity of the pyridine N atom and the carbonyl C atom of the phenylbenzoyl residue, with non-bonded distance N s C of only 2.465(2) Å. A secondary, but significant distortion, involving displacement of the carbonyl C atom by more than 0.5 Å from the pyrrole ring, was evident. The crystal structure is maintained by C–H s O hydrogen bonds and – interactions.     

Schiff bases and their complexes with metal ions. Part II. Structures of N-n-butyl-2-hydroxy-1-naphthaldimine and bis[N-n-pentyl-2-hydroxy-1-naphthaldiminato]nickel(II)

The Schiff base ligand (1), [C₁₅H₁₇NO] crystallizes in the monoclinic space group P2₁/c witha=10.054(3),b=10.313(3), c=13.173(4)Å, =107.42(4)°,V=1303.2(7)ų,Z=4,Dx=1.159 g cm^–3, and (MoK)=0.674 cm^–1. The C2-O[1.23(1)Å] and C3–C4 [1.33(2)Å] bond lengths are short, due to its quinoidal structure. In the Schiff base nickel complex (2), [Ni(C₁₆H₁₈NO)₂] the asymmetric unit is comprised of two half-complexes. It crystallizes in the triclinic space group witha=5.124(3),b=16.227(3),c=16.886(4)Å, =95.47(8), =96.00(1), =90.71(4)°,V=1389.6(9) ų,Z=2,Dx=1.289 g cm^–3, and (MoK) =12.1 cm^–1. The coordination of the Ni(II) ions are square planar with bond angles between 87.9(1) and 92.1(1)°. The Ni–O and Ni–N distances are 1.819(2), 1.922(2) and 1.823(2), 1.914(3)Å in these two complexes.     

Crystal structures of (I) 2-(9,9-dipropylfluorene-2-yl)-9,9- dipropylfluorene and (II) 2-(1,1-dimethylpropyl)-7- {4-[(1,1-dimethylpropyl)-9,9-diethylfluoren-2-yl]phenyl}-9,9-diethylfluorene and (III) 2-(4-ethylphenyl) -7-[7-(ethylphenyl)-9,9-dipropylfluoren-2-yl]-9,9-dipropylfluorene

The crystal structures of the three fluorene related molecules, (I) 2-(9,9-dipropylfluorene-2-yl)-9,9-dipropylfluorene, [Exalite 384, C₃₈H₄₂], (II) 2-(1,1-dimethylpropyl)-7-{4-[(1,1-dimethylpropyl)-9,9-diethylfluoren-2-yl] phenyl}-9,9-diethylfluorene, [Exalite 404, C₅₀ H₅₈], and (III) 2-(4-ethylphenyl)-7-[7-(ethylphenyl)-9,9-dipropylfluoren-2-yl]-9,9-dipropylfluorene, [Exalite 416, C₅₄H₅₈], have been determined. Structural details reveal a novel new bonding arrangement at the C2 atoms of symmetry-related fluorene moieties in all three molecules producing a linear type array with an inversion center connecting adjacent asymmetric units within each molecule. Exalite 384 is monoclinic, space group P2₁/c with a = 9.002(2) Å, b = 16.275(4) Å, c = 10.525(1) Å, = 103.05(1), and V = 1502.1(5) ų with Z = 4, for d _calc = 1.103 g/cm³. Exalite 404 is triclinic, space group P1 with a = 10.383(1) Å, b = 13.404(2) Å, c = 7.7007(9) Å, = 105.296(9), = 104.23(1), = 73.707(9), and V = 974.9(2) ų with Z = 2, for d _calc = 1.141. Exalite 416 is monoclinic, space group P2₁/c with a = 15.99(10) Å, b = 11.178(8) Å, c = 23.766(4) Å, = 104.21(4), and V = 4117(4) ų with Z = 4, for d _calc = 1.141 g/cm³.     

Hydrogen-bonded coordination network in crystal structures of [Cu(3-PM)4Cl2] and [Cu(4-PM)4Cl]Cl, (PM = pyridylmethanol)

The crystal and molecular structures of [Cu(3-PM)₄Cl₂] (1) and [Cu(4-PM)₄Cl]Cl (2) have been determinated by X-ray crystallography. Complex 1 crystallizes in the triclinic system, space group P–1, with lattice parameters a = 7.972(2) Å, b = 8.293(2) Å, c = 10.707(2) Å, = 105.73(3)°, = 90.04(3)°, = 110.38(3)°, and Z = 1 at 100 K. The coordination geometry of each Cu atom is approximately octahedral formed by four nitrogen atoms of pyridine rings of 3-pyridylmethanol molecules in the equatorial plane and two chlorine atoms occupying the axial positions. The O—HsO, C—HsCl, and O—HsCl intermolecular hydrogen bonds and s stacking link the molecules in 3-D hydrogen-bonded coordination network. Complex 2 crystallizes in the tetragonal system, space group P4/n, with lattice parameters a = 10.464(1) Å, c = 11.339(2) Å, and Z = 2 at 217 K and a = 10.352(1) Å, c = 11.201(2) Å, and Z = 2 at 293 K. The coordination geometry of Cu atom in the [Cu(4-PM)₄Cl]⁺ ion is approximately square pyramidal formed by four nitrogen atoms of pyridine rings of 4-pyridylmethanol molecules in equatorial plane and one chlorine atom in axial position. The O—HsCl and C—HsCl intermolecular hydrogen bonds link the molecules in 2-D hydrogen-bonded coordination network.     

Crystal structures of a series of 3,8-di[-2-aryl-1-azenyl]-1,3,6,8-tetraazabicyclo[4.4.1]undecanes

The crystal and molecular structure of a series of 3,8-di[-2-aryl-1-azenyl]-1,3,6,8-tetraazabicyclo[4.4.1]undecanes (1–5) have been determined by single crystal X-ray diffraction analysis. In all five compounds, the tetraazabicycloundecane portion of the molecule assumes a cage-like, folded structure with the aryltriazene moieties aligned approximately parallel; the structure is held in the folded configuration by either intramolecular or intermolecular – stacking forces. Crystal data: 1 C₁₉H₂₂N₁₀O₄, monoclinic space group P2₁/c, a = 10.1846(7), b = 9.9556(7), c = 20.819(2) Å, = 98.725(1)°, V = 2086.5 (3) ų, Z = 4; 2 C₂₃H₂₈N₈O₄, triclinic, space group P, a = 6.7064(7), b = 12.9662(14), c = 14.054(2) Å, = 94.796(2), = 91.621(2), = 104.836(2)°, V = 1175.7(2) ų, Z = 2; 3 C₁₉H₂₂N₁₀O₄, monoclinic, space group P2₁/c, a = 14.237(2), b = 13.520(2), c = 11.5805(12) Å, = 113.514(2)°, V = 2044.0(4) ų, Z = 4; 4 C₂₁H₂₂N₁₀, monoclinic, space group C2/c, a = 54.247(3), b = 11.5531(7), c = 12.9670(7) Å, = 95.710(1)°, V = 8086.4(8) ų, Z = 16; 5 C₂₅H₃₂N₈ 0₄, monoclinic, space group P2₁/c, a = 10.2908(7), b = 16.5687(12), c = 15.1662(10) Å, = 94,188(1)°, V = 2579.0(3) ų, Z = 4.     

X-ray crystal structures of [HB(3,4,5-Me3pz)3[2Zn, [H2B(3,4,5-Me3pz)2]Zn(μ-3,4,5-Me3pz)2Zn[H2B(3,4,5-Me3pz)2], and [H2B(pz)2]2Zn (pz = pyrazolyl ring)

[HB(3,4,5-Me₃pz)₃]₂Zn (1) and [H₂B(3,4,5-Me₃pz)₂]Zn(-3,4,5-Me₃pz)₂Zn[H₂B(3,4,5-Me₃pz)₂] (2) are present in equal amounts in a crystal in the triclinic space group, P-1 with a = 11.5924(11) Å, b = 12.7799(12) Å, c = 15.7317(14) Å = 107.905(2)° = 96.796(2)°, = 105.786(2)°, and Z = 1. The structure of 1 is a trigonally distorted octahedron and is very similar to the structure of [HB(3,5-Me₂pz)₃]₂Zn showing that the introduction of the third methyl group on the pyrazolyl ring does not impact on structure. [H₂B(pz)₂]₂Zn (3) is orthorhombic, Pca2(1) with a = 10.1473(3) Å, b = 11.1117(2) Å, c = 14.1831(5) Å, = = = 90° and Z = 4. The zinc(II) centers in both 2 and 3 are similar and have pseudotetrahedral structures.     

Synthesis and crystal structure of a terephthalato-bridged copper(II) complex [Cu2(tpt)(bpy)2(H2O)4] [Cu2(tpt)3 (bpy)2(H2O)2]

A terephthalato-bridged copper(II) complex [Cu₂(tpt)(bpy)₂(H₂O)₄][Cu₂(tpt)₃(bpy)₂ (H₂O)₂] (1) (tpt = terephthalate, bpy =; 2,2'-bipyridine) was synthesized by the reaction of Cu(ClO₄)₂ 6H₂O and terephthalic acid in the presence of 2,2'-bipyridine in H₂O solution. Crystal structure of 1 was determined by X-ray diffraction analysis in the triclinic space group P , with a = 10.7327(10) Å, b = 11.1658(11) Å, c = 17.3768(16) Å, = 108.063(2), = 91.064(2), = 116.721(2), V = 1737.5(3) ų, and Z = 2. Both the anion and the countercation in 1 are copper(II) complexes linked by terephthalate bridges in the bis(monodentate) (syn–anti) mode. The anion and the countercation are also linked by two hydrogen bonds between coordinating water molecules and terephthalate ligand.     

Structure and characterization of hexakis(imidazole) cobalt(II) complexes: [Co(Im)6(OBz)2] and [Co(Im)6(mB)2] (Im = imidazole, OBz = benzoate, mB = p-methoxybenzoate)

The crystal and molecular structures of the complexes of [Co(Im)₆(OBz)₂] and [Co(Im)₆(mB)₂] (Im = imidazole, OBz = benzoate, mB = p-methoxybenzoate) have been determined by X-ray crystallography. The crystal structures are very similar and consist of discrete molecules of [Co(Im)₆(OBz)₂] and [Co(Im)₆(mB)₂], respectively. They both crystallize in the triclinic system, space group the former with lattice parameters a = 7.6934(3), b = 10.4518(5), c = 11.6088(5) Å, = 73.920(1), = 79.023(1), = 73.681(1)°, and Z = 1; the latter with a = 9.8336(3), b = 10.5509(2), c = 10.8889(3) Å, = 61.450(1), = 76.832(1), = 71.157(1)°, and Z = 1. The cobalt(II) ions have octahedral geometry with a CoN₆ chromophore. In the solid state, the complexes all form a three-dimensional network through N—H···O hydrogen bonds. The electronic spectra and IR spectra data are in agreement with the structural data.     

Structures of 355-1355-1355-1tricarbonyl: structural evidence for the near-electroneutrality of the dialkylacetal substituent

The structures of the (benzene dialkylacetal)tricarbonyl chromium complexes [⁶-C₆H₅-CH(OR)₂]Cr(CO)₆ (R=Me,1; Et,2), are reported. The compounds were examined as part of a study of the conformations of the tripodal tricarbonylchromium group. For [⁶-C₆H₅-CH(OMe)₂]Cr(CO)₃,1, monoclinic,P2₁/c (# 14),a=15.235(1) Å,b=6.5304(5) Å,c=12.702 Å, =103.197(1)^o,Z=4. For [⁶-C₆H₅-CH(OEt)₂]Cr(CO)₃,2, monoclinic,P2₁/c (# 14),a=9.859(3) Å,b=10.547(3) Å,c=15.138(3) Å, =108.42(2)^o,Z=4. The data show that the molecules adopt the expected three-legged piano stool structure. The carbonyl ligands in1 adopt an eclipsed arrangement with respect to the arene ring and its substituent, while those in2 are staggered. These conformations are consistent with the notion that the acetal substituent behaves largely as an electroneutral group, or at most as a weak electronic acceptor.     

Synthesis and structure of 4-R,5-R-[5-(hydroxy-diphenyl-methyl)-2, 2-dimethyl-[1,3]dioxolan-4-yl]-phenyl-methanone, a chiral ligand building block

A triphenyl analog of taddol, 4-R,5-R-[5-(hydroxy-diphenyl-methyl)-2,2-dimethyl-[1,3]dioxolan-4-yl]-phenyl-methanone, has been synthesized and structurally characterized. This molecule could act as a chiral ligand building block in the creation of tuned taddol analogs. Structural analysis of the title compound reveals that the hydroxyl group is involved in an intramolecular hydrogen bond and does not take part in any intermolecular interaction. Crystal packing is influenced by C–H O hydrogen bonding and phenyl phenyl interactions. Crystal data: Triclinic, P1 (No. 1), a = 5.9343(4) Å, b = 8.2367(17) Å, c = 10.987(2) Å, = 88.290(6), = 75.442(4), = 80.655(6), V = 512.86(15) ų, Z = 1, D _calc = 1.258 mg/m³. Final residual values were R ₁ = 0.0407 for 3022 observed data (I > 2s(I) ) and wR ₂ = 0.0941 for all 3524 unique data.     

Self-assembly in transition metal complexes: structural characterization of a copper histamine nitrate [Cu(II)(him)2(NO3)2]

A new monomeric copper (II) complex with histamine (him), [Cu(II)(him)₂(No₃)₂], has been prepared by the reaction of Cu(NO₃)₂ with histaminium dichloride and its structure was determined by x-ray crystallography. The complex crystallizes in the triclinic system, space group with a = 5.7238(4), b = 8.7094(7), c = 9.2481(11) Å, = 69.693(8), = 73.242(7), = 71.050(7)°, V = 400.84(6) ų, and Z = 1. The structure consists of discrete [Cu(II)(him)₂(NO₃)₂] molecules in which the metal atom is centrosymmetrically coordinated by two histamine ligands forming an equatorial plane with Cu–N(imidazole ring) being 2.032(2) and Cu–N(NH₂ group) being 2.023(2) Å. Two O atoms from nitrate anions coordinate on the elongated axial positions with Cu–O being 2.549(2) Å. In the crystal structure, the molecules are organized by hydrogen bonds forming a two-dimensional network.     

Synthesis and crystal structures of quadruply carboxylate-bridged dimeric lanthanide(III) complexes of betaine

Three dimeric lanthanide(III) complexes, [Eu₂(bet)₈(H₂O)₄](CIO₄)₆ (1), [Tb₂(bet)₈(H₂O)₄](ClO₄)₆ (2), and [Eu₂(bet)₄(H₂O)₈] Cl₆·6H₂O (3) (bet = Me₃N⁺CH₂COO^–, trimethyl-aminoacetate), have been prepared and structurally characterized by X-ray crystallography. Complex 1 crystallizes in the monoclinic space group P2₁/c, with a = 11.7807(8), b = 27.757(5), c = 11.7980(8) Å, = 99.500(4)°, V = 3805.1(8) ų, and Z = 2. Complex 2 is isomorphous to complex 1, crystallizing in the monoclinic space group P2₁/c, with a = 11.7769(14), b = 27.725(3), c = 11.795(5) Å, = 99.668(14)°, V = 3797(2) ų, and Z = 2. Complex 3 crystallizes in the orthorhombic space group Pbca, with a = 12.5664(8), b = 17.8645(9), c = 22.2573(8) Å, V = 4996.6(4) ų and Z = 4. Both complexes 1 and 2 comprise quadruply carboxylate-O,O-bridged [M₂(bet)₄]⁶⁺ dimeric cores (M = Eu, Tb), and each metal ion is further coordinated by two terminal aqua ligands and two monodentate bet carboxylates to form a distorted square-antiprismatic coordination geometry. Complex 3 also has a [Eu₂(bet)₄]⁶⁺ core, in which two bet ligands act in the ¹:¹:₂ bridging fashion, and the other two bet ligands in the less common ²:¹:₂ bridging fashion, namely bridging-chelate mode. Each europium(III) ion in complex 3 is further coordinated by four water molecules to complete a monocapped square antiprism.     

Synthesis and structures of two chiral bis(pyrazolyl)borate complexes, [{H<Subscript>2</Subscript>B(4-Mepz)(3,5-Me<Subscript>2</Subscript>pz)}<Subscript>2</Subscript>M], M = Co,Zn

The title compounds are chiral and have similar molecular geometries. The Co complex crystallizes in space group P2₁/c with a = 8.475(4) Å, b = 7.706(8) Å, c = 35.778(9) Å, = 95.779(18) and Z = 4, while the Zn complex crystallizes in space group P2₁/n with a = 8.353(3) Å, b = 20.768(4) Å, c = 13.818(3) Å, = 100.96(2) and Z = 4. The metal atoms are tetrahedrally coordinated to two bidentate ligands with M–N distances in the ranges 1.985(2)–2.018(2) Å (Co) and 1.985(2)–2.008(2) Å (Zn), and N–M–N angles in the ranges 96.07(7)–128.23(7) (Co) and 98.50(8)–125.63(8) (Zn). No agostic bonds are formed. The molecules display C₁ symmetry; geometric considerations indicate that the formation of the other two possible conformers, with C₂ symmetry, is sterically less favorable.     

The structure of 2-amino-3-cyano-4-(4-methylphenyl)-6-methoxyl-1,4,9,10-tetrahydrobenzo[<Emphasis Type="Italic">f</Emphasis>]chromene

The X-ray crystal structure of 2-amino-3-cyano-4-(4-methylphenyl)-6-methoxyl-1,4,9,10-tetrahydrobenzo [f]chromene 1, C₂₂H₂₀N₂O₂, is determined. The crystals of compound 1 are triclinic, space group P-1, a = 10.120(1), b = 13.127(1), c = 15.203(2) Å, = 67.841(9), = 80.81(1), = 77.58(1), Z = 4, V = 1819.7(4) ų. It is interesting that all the atoms of the pyran ring are coplanar, which is different from other similar compounds. The structure is stabilized by intermolecular hydrogen bonds.     

Crystal structure of bis[dihydrobis(3,5-dimethy-1-pyrazolyl)borato]cadmium(II)

The structure of [H₂B(3,5-Me₂pz)₂]₂Cd shows the four nitrogen donor atoms form a pseudotetrahedral arrangement about the cadmium(II). The intraligand N—Cd—N angles are restricted to an average of 91.4° by the chelate rings forcing the interligand N—Cd—N bond angles to average 119.4°. The Cd—N bond distances average 2.21 Å with a range of 0.04 Å. The crystal is in the triclinic space group, P with a = 7.6793(2) Å, b = 8.5992(2) Å, c = 25.0874(4) Å, = 91.0791(2)°, = 97.9769(4)°, = 110.2344(6)°, and Z = 2.     

Synthesis and structural characterization of the bitopic ferrocene-based tris(pyrazolyl)methane ligand Fe[C5H4CH2OCH2C(pz)3]2 (pz = pyrazolyl ring)

The structure of Fe[C₅H₄CH₂OCH₂C(pz)₃]₂ (pz = pyrazolyl ring) contains 1.5 independent molecules in the asymmetric unit. One molecule has no imposed symmetry with the iron atom located on a general position while in the other the iron atom is located on an inversion center. The two independent molecules are arranged into a three-dimensional supramolecular structure by a series of C—H s N and C—H s O weak hydrogen bonding interactions and C—H s interactions. The crystals are triclinic, space group, P , with a = 8.1202(4) Å, b = 16.7209(9) Å, c = 18.6540(10) Å = 85.8270(10), = 85.4740(10), = 81.5910(10), and Z = 3     

Structure of 2-{2-[3-methyl-3-(2,4,6-trimethylphenyl) cyclobutyl]-2-oxoethyl}isoindole-1,3-dione

2-{2-[3-Methyl-3-(2,4,6-trimethylphenyl)cyclobutyl]-2-oxoethyl}isoindole-1,3-dione (C₂₄ H₂₅NO₃) was synthesized, and its crystal structure was determined by X-ray crystallographic techniques. The compound crystallizes in the triclinic space group P-1, with unit cell parameters: a = 14.109(9) Å, b = 14.130(8) Å, c = 12.152(6) Å, = 105.62(5)°, = 113.75(4)°, = 98.78(5)°, V = 2039.8(19) ų, D _c= 1.223 g/cm³, and Z = 4. The crystal structure has two crystallographically independent molecules, I and II. These molecules are held together by weak intermolecular C—H···O interactions, forming a continuous chain. The dihedral angles between the N-substituted phthalimide moiety and cyclobutane ring in molecules I and II are 60.37(14) and 68.18(18)°, respectively.     

Complexation with diol host compounds. Part 3. Molecular inclusion of 4-methylcyclohexanone and 2-methylcyclohexanone by the host,trans-9,10-dihydroxy-9,10-diphenyl-9,10-dihydroanthracene

The structures of the 12 molecular complexes oftrans-9,10-dihydroxy-9,10-diphenyl-9,10-dihydroanthracene with 4-methylcyclohexanone (1) and with 2-methylcyclohexanone (2) have been determined by X-ray crystallography. The crystal data are as follows: Compound (1):P2₂/c,a=8.838(2) Å,b=8.92(1) Å,c=20.879(8)=Å,=98.67(2)°,V=1627(2) ų,Z=2 andR=0.062 for 2201 unique MoK reflections; Compound (2):P¯1,a=8.917(3) Å,b=9.900(2) Å,c=11.250(4) Å,a=68.72(2)°,=64.39(3)°, =74.86(2)°,V=828.1(5) ų,Z=1 andR=0.098 for 2563 unique reflections. Both inclusion compounds exhibit O-HO=C hydrogen bonding interactions. The thermal properties of these compounds have been characterized by DTA and TGA thermograms.     

Synthesis and molecular structure of [Al(CH3)2]2[C10H22N4] [Al(CH3)3]2: Condensation product of trimethylaluminum and a multidentate open-chain amine

The crystalline condensation product [Al(CH₃)₂]₂[C₁₀H₂₂N₄][Al(CH₃)₃]₂ is prepared from reaction of the multidentate open-chain amine 1,4-bis(3-aminopropyl)piperazine with trimethylaluminum in methylene chloride. The compound crystallized in the monoclinic space groupC2/c with unit cell parametersa=25.166(12),b=7.268(4),c=17.316(4) Å,=115.3(4)°, andD _c =1.06 g cm^–3 forZ=4. Least-squares refinement based on 1054 observed reflections with intensitiesI 3(I) in the range 2<2<45° led to a finalR factor of 0.053 (R _w =0.064). The title compound resides on a crystallographic center of symmetry with independent Al-N distances of 1.889(5), 2.058(5), and 2.030(5) Å.