Crystal and molecular structures of (±)cadinene dihydrochloride (1) and (−)cadinene dihydrochloride (2)

Two compounds, racemic (±)cadinene dihydrochloride C₁₅H₂₆C1₂ (1) and (–)cadinene dihydrochloride C₁₅H₂₆Cl₂ (2), prepared by treating germacrene D fromSolidago canadensis L, and sesquiterpene fraction of essential oil fromPinus silvestris L, respectively, with gas HCl were investigated. Compound (1) crystallizes in monoclinic system, but (2) in orthorhombic (Table 1). The structures were found by direct methods and were refined with full matrix least-squares techniques to R value of 0.039 and 0.044, respectively, for (1) and (2).     

Crystal and Molecular Structures of 2-Amino-4-Nitrobenzoic Acid and Its Cocrystals with 2,2′-Bipyridine (2/1) and Bis(pyridin-2-yl)ketone (1/1)

Abstract  

The eight-membered {···HOC=O}₂ synthon featured in the crystal structure of 2-amino-4-nitrobenzoic acid (1) is replaced by carboxylic acid···N-pyridine hydrogen bonds in its cocrystals with 2,2′-bipyridine (2/1; 2) and bis(pyridin-2-yl)ketone (1/1; 3) indicating the robust nature of the latter synthon. Disruption of the three-dimensional architecture based on O–H···O and N–H···O(nitro) hydrogen bonds in (1) is evident in the cocrystals which form supramolecular tubes (2) and chains (3) based on O–H···N and N–H···O hydrogen bonding. Compound (1) crystallizes in the monoclinic space group P2₁/n with a = 3.6291(1) ?, b = 7.7339(3) ?, c = 26.561(1) ?, β = 91.385(2)°, and Z = 4. Compound (2) crystallizes in the monoclinic space group C2/c with a = 27.562(3) ?, b = 6.8300(6) ?, c = 12.923(1) ?, β = 110.593(5)°, and Z = 4. Compound (3) crystallizes in the monoclinic space group P2₁/c with a = 3.795(3) ?, b = 12.024(8) ?, c = 35.65(2) ?, β = 92.131(6)°, and Z = 4 (determined from synchrotron data).     

Molecular structure of N-(2-phenylethyl)amide of α-(1,1-ethylenedioxy)-ethyl γ-hydroxybutyric acid (I) and1H NMR spectra of (I) and N-(p-methoxybenzyl)derivative (III)

The spectroscopic and X-ray investigation of the N-(2-phenylethyl) amide of -(1,1-ethylenedioxy)-ethyl--hydroxybutyric acid are reported. The¹H NMR spectra for the title structure and for the N-(p-methoxybenzyl) amide of -(1,1-ethylenedioxy)-ethyl--hydroxybutyric acid are given. The N-(2-phenylethyl)amide of -(1,1-ethylenedioxy)-ethyl--hydroxybutyric acid, C₁₆H₂₃O₄N, crustallizes in the monoclinic space groupP2 ₁/c witha=21.547(5),b=6.333(2),c=11.822(3) Å and =101.01(2)°. The dioxolane ring has a half-chair conformation with C₂(O3)=2.4° and ||_av=18.2°. The inconsiderable deviations from planarity of the six atoms of the amide group are caused mainly by twist around the C4–N1 bond and out-of-plane bending at the N1 atom ((C4–N1)=4°, X_N =7°, X_c =0.4° ). The amide group plane is nearly coplanar with the phenyl ring. The molecules are connected by two intermolecular hydrogen bonds.     

Growth and Study of Properties of Mixed Crystals (NH4)2NixCo1 –x(SO4)2 · 6H2O

Crystallography Reports - Mixed crystals (NH4)2NixCo1 –x(SO4)2 · 6H2O have been grown from aqueous solutions of different compositions by reducing the solution temperature in two growth...     

Structures of threo(RR,SS) diethyl ester of 2-hydroxy-1,2-diphenylethylphosphonic acid and (±)diethyl ester of (1-hydroxycyclopentyl)(2-methylphenyl)methylphosphonic acid

The crystal structures of threo(RR,SS) diethyl ester of 2-hydroxy-1,2-diphenylethylphosphonic acid (1) and of (±)diethyl ester of (1-hydroxycyclopentyl)(2-methylphenyl)methylphosphonic acid (2) have been solved by X-ray methods. They are built up in a similar way to centrosymmetric dimers of hydrogen-bonded molecules. The orientation of the substituents around the central C-C bond in both molecules fulfills the requirement for the least spatial hindrance. The observed shift of the _oh stretching frequencies from 3312(1), 3346 (2) cm^–1 in solid to 3408(1), 3450(2), in diluted (10^–3 M) tetrachloromethane solution, indicates the formation of intramolecular hydrogen-bonded species.     

Preparation and crystal structure of spiro(5,7-dimethoxy-1(1H)oxo-2-benzopyran-3(4H),1′-cyclohexane)

Spiro(5,7-dimethoxy-1(1H)oxo-2-benzopyran-3(4H),1-cyclohexane) (C₁₆H₂₀O₄) was prepared by alkylation of o-lithio 3,5-dimethoxy-N-methyl benzamide with methylene cyclohexane oxide followed by alkaline hydrolysis and its crystal structure was determined by X-ray crystallographic techniques. The compound crystallizes into monoclinic space group P2₁/c with unit cell parameters: a = 11.914(3) Å, b = 9.861(3) Å, c = 12.508(7) Å, = 91.34(3), Z = 4. The structure has been solved by direct methods and refined to R = 0.039 for 1870 observed reflections. The heterocyclic ring adopts distorted sofa conformation while cyclohexane ring assumes a highly symmetric chair conformation. The dihedral angle between the mean planes of isocoumarin nucleus and cyclohexane ring is 105.51(5). Molecules are held together in the crystal by C=H ... O hydrogen bonds.     

Investigation of the structure and properties of (K x (NH4)1 − x )3H(SO4)2 single crystals

The influence of isomorphous replacement in the cation sublattice on the kinetics of the phase transition in single crystals of the solid solutions (K _x (NH₄)_{1 ? x} ) _m H _n (SO₄)_{(m + n)/2} · yH₂O belonging to the K₃H(SO₄)₂-(NH₄)₃H(SO₄)₂-H₂O salt system was studied. Superproton phase transitions for the end compositions of this system have been found earlier. The optical and thermal properties of crystals with the composition (K,NH₄)₃H(SO₄)₂ in the temperature range from 295 to 500 K were investigated, and the crystal structure was determined at 295 K. The results of the study and the comparison with the literature data show that the replacement of potassium atoms with ammonia leads to a fundamental change in the kinetics of the phase transition, the phase-transition temperature remaining virtually unchanged.     

Electrical properties of glass and liquid semiconductor system (As2Te3)x(Tl2Se)1−x

We have measured the electrical conductivity and thermoelectric power of the pseudobinary system (As₂Te₃)_x(Tl₂Se)_1−x both in the glass and liquid states. The effect of the addition of excess Tl has also been examined. It has been found that the activation energy of electronic conduction is closely related to the average atomization energy of these materials.     

Characterization of an asymmetric M(chelate)2(μ-Cl)2MCl2 dimer and isolation of corresponding DMSO adducts: X-ray crystal structures of Co(phen)2(μ-Cl)2CoCl2⋅C4H8O and M(chelate)Cl2(DMSO) x (Co, x = 1; Ni, x = 2) complexes

In aqueous solution, [M(chelate)Cl₂]x (chelate = 2,2-bipyridine, 1,10-phenanthroline) complexes can disproportionate to produce M(chelate)₂ ⁿ⁺ species that contain two chelating ligands. After extraction with organic solvent,Co(phen)₂(-Cl)₂CoCl₂(1) has been characterized by X-ray diffraction (monoclinic, C2/c, a = 10.278(2)Å, b = 22.026(5)Å, c = 12.941(3)Å, = 103.959(4)°, Z = 4, 2414 reflections [I 2 (I)], R ₁ = 0.0321, wR ₂ = 0.0864). However, addition of [M(chelate)Cl₂]x starting materials to dimethyl sulfoxide produces complexes that retain a single chelate ligand. The pentacoordinate complex Co(bpy)Cl₂DMSO (2) has been structurally characterized (triclinic, P , a = 7.824(2)Å, b = 9.570(4)Å, c = 10.025(2)Å, = 83.24(3)°, = 87.14(2)°, = 83.35(3)°, Z = 2, 2455 reflections [I 2 (I)], R ₁ = 0.0278, wR ₂ = 0.0747). In the case of nickel, two different geometric isomers are observed, depending on the chelate identity: trans-(DMSO)₂Ni(bpy)Cl₂ DMSO (3) (monoclinic, P21/c, a = 10.9149(8)Å, b = 12.1287(9)Å, c = 17.0044(13)Å, = 98.610(1)°, Z = 4,3519 reflections [I 2 (I)], R ₁ = 0.0209, wR ₂ = 0.0560) and cis-(DMSO)₂Ni(phen)Cl₂ (4) (monoclinic, P21/c, a = 8.404(2)Å, b = 14.051(4)Å, c = 16.710(4)Å, = 92.44(3)°, Z = 4, 3069 reflections [I 2 (I)], R ₁ = 0.0691, wR ₂ = 0.1782).     

Crystal and molecular structure of the H-bonded complex between 1-chloro-2-hydroxynaphthalene-3-carboxylic acid and dimethylformamide (1∶1)

Crystal structure determination of the title complex reveals that the dimethylformamide solvent is bound to the carboxylic function of the hydroxy acid, in the form of a 7-membered hydrogen-bonded loop involving both the expected O-HO and an apparently weak C-HO interaction between host and guest. There is a strong intramolecular hydrogen bond between the phenolic OH and the carbonyl oxygen. Close packing of the complex units is afforded by a herringbone type alignment of host molecules.     

Syntheses and Crystal Structures of Two CuII Coordination Isomers [Cu(pmt)2] · 4H2O (1) and {[Cu(pmt)2] · 2H2O} n (2)

Abstract  A pair of Cu^II coordination isomers [Cu(pmt)₂] · 4H₂O (1) and {[Cu(pmt)₂] · 2H₂O} _n (2) [Hpmt = 2-(2-pyridylmethylamino) ethanesulfonic acid] have been prepared by reaction of the same proportion CuCl₂ · 2H₂O and Hpmt but with different experimental methods in water–methanol mixed solution, and were characterized by X-ray diffraction, elemental analysis, IR spectrum. X-ray analysis indicates that complex (1) is a mononuclear complex in which two deprotonated pmt ligands coordinate in a facial tridentate arrangement about the Cu^II atom. While complex (2) is a coordination polymer, in which four N atoms of pmt ligands coordinate to one Cu^II atom but its sulfonate O atoms bond to adjacent Cu^II atom. Thus 12-membered rings (–Cu–N–C–C–S–O–)₂ are obtained between two neighbouring Cu^II atoms and they connect one another to form this new polymer. Crystal data: [Cu(pmt)₂] · 4H₂O (1), Mr = 566.10, monoclinic, P2 ₁/c, a = 9.1950(8) ?, b = 11.5093(10) ?, c = 11.2304(10) ?, β  = 105.5550(10)°, Z = 2, V = 1144.96(17) ?³, R ₁  = 0.0407, wR ₂  = 0.1242 [I > 2σ (I)]; {[Cu(pmt)₂] · 2H₂O} _n (2), Mr = 530.07, triclinic, P-1, a = 7.6165(19) ?, b = 8.806(2) ?, c = 9.592(4) ?, α = 104.933(4)°, β = 106.732(4)°, γ = 109.503(3)°, Z = 1, V = 534.2(3) ?³, R ₁ = 0.0470, wR ₂ = 0.1082 [I > 2σ(I)]. Index Abstract  A pair of Cu^II coordination isomers [Cu(pmt)₂] · 4H₂O (1) and {[Cu(pmt)₂] · 2H₂O} _n (2) [Hpmt = 2-(2-pyridylmethylamino) ethanesulfonic acid] have been prepared by reaction of the same proportion CuCl₂ · 2H₂O and Hpmt but with different experimental methods in water–methanol mixed solution.      

Synthesis and structure of (H2O·HBF4)2(18-crown-6)

The title compound has been prepared by the addition of fluoroboric acid to 18-crown-6 in toluene. The compound crystallizes in the triclinic space group P¯1 witha=7.341(2),b=8.364(2),c=10.631(3)Å,=71.48(2),=67.91(2), =67.94(2)°, andD _c =1.44 g cm^–3 forZ=1. The final conventionalR value was 0.079 based on 1575 observed reflections. The molecule resides on a center of inversion. The (H₂O·HBF₄) moieties are best viewed as fluoroboric acid monohydrate molecules hydrogen bonded to the crown ether, one above and one below the plane of the crown. The FO(water) hydrogen bond separation is 2.474(5)Å, and the O(crown)O(water) separations are 2.834(5) and 2.841(6) Å. The oxygen atoms of the crown ether are planar to 0.23 Å.     

Self-assemblies of Ni(II) with phenanthroline and maleate anions: [Ni(H2O)3(phen)L] ⋅ H2O (1) and [Ni(H2O)2(phen)L] ⋅ 2H2O (2) with H2L = maleic acid

The complex [Ni(H₂O)₃(phen)(C₄H₂O₄)] H₂O (1), which was obtained by reaction of phenanthroline, Ni(NO₃)₂ 6H₂O, and maleic acid in CH₃OH/H₂O at pH = 7.05, crystallized in the monoclinic space group P2₁ (no. 4) with cell dimensions: a = 9.350(1) Å, b = 7.631(1) Å, c = 12.821(1) Å, = 106.25(1), and D _calc = 1.607 g/cm³ for Z = 2. The Ni atoms are each octahe drally coordinated by one chelating phen ligand, three H₂O molecules and one monodentate maleato ligand to form [Ni(H₂O)₃(phen)(C₄H₂O₄)] complex molecules with d(Ni–O) = 2.038–2.090 Å, d(Ni–N) = 2.066, 2.089 Å. The formed complex molecules are, via the intermolecular hydrogen bonds, assembled into columnar 1D chains. Interdigitation of the chelating phen ligands of the neighboring chains leads to 2D layers and the crystal H₂O molecules are hydrogen bonded to the oxygen atoms of the maleate not coordinated to the Ni atom. However, reaction of NiCO₃, phen, and maleic acid in CH₃OH/H₂O at pH = 6.33 afforded [Ni(H₂O)₂(phen)(C₄H₂O₄)] 2H₂O (2), which crystallized in the triclinic space group (no. 2) with cell dimensions: a = 7.971(1) Å, b = 8.237(1) Å, c = 13.304(1) Å, = 81.005(6)°, = 87.877(8)°, = 78.322(8)°, and D _calc = 1.671 g/cm³ for Z = 2. The Ni atoms are each octahedrally coordinated by two N atoms of one phen ligand and four O atoms of two H₂O molecules and two bis–monodentate maleato ligands with d(Ni–O) = 2.041–2.120 Å and d(Ni–N) = 2.095 Å. The Ni atoms are bridged by the maleato ligands to generate 1D ¹ [Ni(H₂O)₂(phen)(C₄H₂O₄)_2/2] chains along [100]. The supramolecular assemblies of the 1D chains via – stacking inter- actions result in thick 2D layers parallel to (001), between which the noncoordinating H₂O molecules are sandwiched. The paramagnetic [Ni(H₂O)₂(phen)(C₄H₂O₄)_2/2] 2H₂O (2) obeys the Curie–Weiss law _m(T-) = 1.139cm³ mol^–1 K with the Weiss constant = –0.95 K.     

Reactions of [Mn2(μ-pyS)2(CO)6] (pySH=pyridine-2-thiol) with triphenylphosphine (PPh3), diphenylphosphine (PHPh2) and bis(diphenylphosphino)methane (dppm): X-ray crystal structure of [Mn(pyS)(η1-dppm)2(CO)2]

The dimeric complex [Mn₂(-pyS)₂(CO)₆] (1) reacted with 2 M equivalents of both PPh₃ and PHPh₂ to give the respective monomeric phosphine complexes [Mn(pyS)(L)(CO)₃][L = PPh₃ (2) and PHPh₂ (3)]; with 4 M equivalents of dppm, it yielded the complex [Mn(pyS)(¹-dppm)₂(CO)₂](4). An X-ray structure determination of 4 shows that it crystallizes in the monoclinic space group P2₁/n with a = 11.027(3), b = 24.984(7), c = 18.379(5) Å, = 99.870(8)°, V = 4988(2) ų, and Z = 4. The complex has an octahedral geometry with the chelating pyS ligand and two CO groups occupying the equatorial sites and the two monodentate dppm ligands lying in the trans positions.     

Synthesis and Structure of 1-Chlorosulfonyl-2-(4′-Nitrophenoxy)-5-Methylbenzene

Abstract  Diphenyl ethers are structural elements found in medicinally useful antibiotics such as vancomycin as well as in biological toxins in the environment such as dioxins. The purpose of this paper is to report the synthesis and characterization of the previously unreported 1-chlorosulfonyl-2-(4′-nitrophenoxy)-5-methylbenzene, a trisubstituted diphenyl ether derivative. ¹H NMR (CDCl₃) δ 2.45 (3H, methyl₅, s), 7.07 (1H, H₄, d, J ~8.27 Hz), 7.13 (2H, H_2′, H_6′, d, J ~9.0 Hz), 7.54 (1H, H₃, d, J ~8.28 Hz), 7.87 (1H, H₆, s), 8.22 (2H, H_3′, H_5′, J ~9 Hz); ¹³C NMR (CDCl₃) δ 20.7, 118.2, 121.9, 126.0, 129.8, 135.2, 135.8, 137.8, 143.8, 150.3, 161.4. An X-ray analysis has provided valuable insight into the effect of steric factors on the three dimensional shape of this compound which serves as a useful advanced intermediate in the synthesis of these biologically active molecules. A multistep synthesis of this molecule has been designed by retrosynthetic analysis as part of an ongoing program aimed at a function-oriented, multi-step economical synthesis of vancomycin lead antibiotics. Crystals are triclinic, space group P-1, a = 7.6537(15), b = 8.976(2), c = 11.050(2) ?, α = 67.645(11), β = 79.735(11), γ = 87.798(10)°, V = 690.5(2) ?³, Z = 2. Graphical Abstract  The synthesis and characterization of the previously unreported trisubstituted diphenyl ether derivative are reported. The phenyl rings form a dihedral angle of 64.49(4)° and the chlorosulfonyl group has a C–C–S–Cl torsion angle of 62.95(11)°.      

X-ray and NMR structural investigations of (±) (u) N-(1-phenylethyl)-1-t-butylsulfinyl-1-propenyl-2-amine,C15H23NOS

The structure of the title compound has been investigated in the solid state and in solution by X-ray and NMR-NOE methods, respectively. The crystals are monoclinic:P2₁/c,a=9.828(1),b=12.326(2),c=13.976(2) Å,=107.36(1)°. The structure was solved by direct methods, and refined against 2495 unique reflections by a full-matrix, least-squares procedure givingR=0.046. In the solid state the compound exists as theE isomer with unlike relative configurations on asymmetric atoms. In solution the compound is found as a mixture of a single enamine and two imine forms. The MM calculations suggest that of the two possible geometrical isomers of both diastereoisomersu andl of the enamine, theZ forms should be of lower energy. The total recognition of the homonuclear¹H NMR-NOE data interpreted in terms of their distance dependence in the two geometrical forms also favors theZ isomer in both diastereomers.     

A comparison of the crystal structures of (dabcoH2)CuCl4 and (dabcoH2)CuCl4⋅H2O

The crystal structures of the anhydrous and monohydrated (dabcoH₂)CuCl₄nH₂O salts (n = 0,1) have been determined and a comparison of their crystal structures has been reported. The anhydrous salt is monoclinic P2₁/c with a = 9.045(2) Å, b = 6.9270(10) Å, c = 18.767(4) Å and = 90.07(3)° with V = 1175.8(4) ų. The hydrated salt is also monoclinic P2₁/c with a = 9.266(2) Å, b = 9.395(2) Å, c = 14.386(3) Å and = 93.32(3)° with V = 1250.3(5) ų. The structures of the two salts are closely related. Both compounds contain isolated distorted (compressed) tetrahedral CuCl₄ ^2– anions, diprotonated dabco cations, and in the case of the hydrated salt, lattice H₂O molecules. In the anhydrous salt, each of the two N–H⁺ groups of the dabcoH₂ ²⁺ dications form bifurcated hydrogen bonds to chloride ions on adjacent CuCl₄ ^2– anions along the c axis, thus forming chains running parallel to the c axis. In the hydrated salt, a water molecule is inserted into one of the pair of bifurcated hydrogen bonds, forming instead N–H O–H CuCl₄ ^2– linkages. The chains thus formed are cross-linked by O–H Cl hydrogen bonds between the chains. Because of this additional hydrogen bonding, the CuCl₄ ^2– anions in the hydrated salt are distorted further from tetrahedral geometry.     

Synthesis and Structural Characterization of [2-(2-1H-Imidazoly)-1H-imidazolium nitrate] and [2-(2-1H-Imidazoly)-2H-imidazolium phthalyl glycinate] Based on the 2,2′-bi-1H-Imidazole Molecule

Abstract  

Two new compounds (H₃biim)(NO₃)(1) and (H₄biim)(phthgly)₂ (2) (H₂biim=biimidazole; Hphthgly=N-phthaloylglycine) have been synthesized and characterized by luminescence and single crystal X-ray diffraction study. Compound 1 crystallizes in the monoclinic space group C2/c, where a = 14.8078(15), b = 5.9233(6), c = 20.028(2) ?, β = 92.7910(10)°, V = 1754.6(3) ?³ and Z = 8. Compound 2 crystallizes in the monoclinic space group P2(1)/n, where a = 15.3775(14), b = 5.3200(6), c = 6.4689(18)?, β = 115.418(2)° V = 1216.9(2)?³ and Z = 4. In 1, the N–H groups of H₃biim⁺ and the oxygen atoms of NO₃ ⁻ are linked by hydrogen bonds leading to H₃biim⁺(N,N)–R₂²(10) and N–H···O interactions forming infinite 1D helical chains along the b-axis. Compound 2 consists of a planar diprotonated biimidazole moiety and two phthgly anions which connect to the dication by hydrogen bonds phthgly⁻(O,O)–R₂²(9).     

Crystal and molecular structures of the 4-(1H)-pyridone (=L) lanthanide complexes {[GdL(NO3)3(H2O)]·CH3OH}2 and [DyL4(NO3)2](NO3) and of L2HNO3

The crystal structures of the title compounds have been determined by single crystal diffraction methods. Crystals of the dysprosium compound are monoclinic, space groupP2₁/c witha=14.133(4),b=13.438(5),c=14.401 (4)Å,=103.98(2)°,V=2654(1)ų,Z=4,D _c =1.82 g cm^–3, finalR=0.035. The Dy atom is eight-coordinate with a distorted dodecahedral coordination geometry involving two bidentate nitrate groups and four pyridone oxygen atoms. An erbium complex with analogous stoichiometry was also prepared but not structurally characterized. Crystals of the Gd compound are monoclinic, space groupP2₁/n, witha=11.226(2),b=9.075(2),c=16.737(3)Å,=93.88(3)°,V=1701(1)ų,Z=2,D _c =1.91 g cm^–3, finalR=0.042. Each Gd atom is bonded to one pyridone oxygen atom, a water molecule and three bidentate nitrate groups. An oxygen atom of one of the bidentate nitrates additionally serves to bridge pairs of Gd atoms so as to form a dinuclear complex in which each Gd atom is nine-coordinate with a tricapped trigonal prismatic geometry. Crystals of L₂HNO₃ are monoclinic, space groupI2/a witha=12.479(4),b=6.535(2),c=14.297(6)Å,=96.07(3)°,V=1159(1)ų,Z=4,D _c =1.45 g cm^–3, finalR=0.057. The pyridones are linked in pairs by very short (2.44 Å) symmetrical OHO hydrogen bonds. Each pair is further linked via a nitrate ion by means of N-HO(nitrate)H-N hydrogen bonds, so as to form an extended chevron-like pyridone-pyridone-nitrate-pyridone-pyridone array. Adjacent chains are linked via weak C-HO(NO₃) interactions.