Synthesis,Spectral Properties and Structure of New Novel 3,3′-Dibenzoyl-1,1′-(propan-1,3-diyl)-bisthiourea

Abstract  

A new 3,3′-dibenzoyl-1,1′-propan-1,3-diyl)bisthiourea was synthesized by using benzoylisothiocyanate with 1,3-diaminopropane in aprotic solvent. The structure was determinated by means of FT-IR, ¹H-NMR, ¹³C-NMR and mass spectroscopic techniques. The crystal structure of 3,3′-dibenzoyl-1,1′-(propan-1,3-diyl)bisthiourea has also been examined by using X-ray crystallographic techniques and found to be crystallized in the monoclinic space group P2 ₁ /c with the unit cell parameters: a = 5.968(1) ?, b = 19.471(2) ?, c = 16.585(2) ?, β = 98.32(1)°, V = 1907.0(4) ?³, Dx = 1.395 g cm⁻³, and Z = 4 respectively.     

Synthesis and Some Properties of 3-Fluoro-4-Cyanophenyl 4′-n-alkylbenzoates

A series of 3-fluoro-4-cyanophenyl 4′-n-alkylbenzoates, which show monotropic nematic phases, was prepared and their transition temperatures and melting enthalpies were measured. The 3-fluoro-4-cyanophenyl 4′-n-propylbenzoate, 3-chloro-4-cyanophenyl 4′-n-propylbenzoate and 4-cyanophenyl 4′-n-propylbenzoate were mixed with a nematic mixture (A) of 4-n-alkoxyphenyl 4′-n-alkylcyclohexane-1′-carboxylates. 3-Fluoro-4-cyanophenyl 4′-n-propylbenzoate decreases the N-1 transition temperature less, increases the birefringence more, and increases the bulk viscosity less than 3-chloro-4-cyanophenyl 4′-n-propylbenzoate, and reduces the threshold voltage to the greatest extent. The dielectric anisotropies of 3-fluoro-4-cyanophenyl 4′-n-propylbenzoate and 4-cyanophenyl 4′-n-propylbenzoate determined from a series of solutions of the compounds in nematic mixture (A) are 35.9 and 29.6, respectively.     

Synthesis and Mesomorphic Properties of the Homologous Series of Di-(4′- n-alkylphenyl)- trans-cyclohexane-1,4-dicarboxylates

The homologous series of di-(4′- n-alkylphenyl)- trans-cyclohexane-1,4-dicarboxylates in which the alkyl group is C₁-C₁₂ has been prepared by esterification of trans-1,4-cyclo-hexanedicarboxylic acid or dicarbonyl chloride with 4-alkylphenols. Mesomorphic properties and phase transitions as determined by hot-stage polarizing microscopy and DSC are discussed in relationship to various structural features. Comparisons of these properties with those for the corresponding alkoxy series and the analogous terephthalic acid diesters are also presented and discussed.     

Synthesis of Sulfonated Cholesterol Derivatives—Electrical,Thermal, and Optical Properties

Poly(cholesterylacrylatesulfone) (PCHAS) and poly(cholesterylacrylatesulfone-co-1-hexene)s (PCHASHs) at different ratios are synthesized from the monomer cholesteryl acrylate. The liquid crystalline phases are observed under a hot stage fitted with a polarizing optical microscope. The polysulfone and copolysulfones are characterized by FT-IR, ¹H-NMR, DSC, and TGA techniques. From SEM (EDX) the qualitative amounts of elemental sulfur found in PCHAS and PCHASH11 are 2.90 weights (%) and 4.39 weights (%), respectively. The GPC data using THF as the solvent shows that the number average molecular weight of the PCHAS is 5268 g/mol and the molecular weights of the PCHASHs are higher than the PCHAS.     

Synthesis and crystal structure of N,N′-dicyclohexylimidazolium hexafluorophosphate

N,N-dicyclohexylimidazolium hexafluorophosphate was prepared and its structure was determined by X-ray diffraction. The compound crystallizes in the orthorhombic space group Pbca, with the cell dimensions of a = 14.620(3) Å, b = 15.097(3) Å, c = 16.128(3) Å, V = 3559.4(12) ų, and D _calc. = 1.412 mg/m³ for Z = 8. The structure was solved by direct methods and refined to R value of 0.041. In the solid state, PF₆ ^– anion and imidazolium cation form strong hydrogen bonds, which fix the relative orientation between cations and anions.     

The Synthesis of Deuteriated 4-n-Alkyl-4′-Cyanobiphenyls

A single synthetic route for chain-deuteriated, totally ring-deuteriated, or per-deuteriated 4-n-alkyl-4′-cyanobiphenyls has been developed. This new route gives better yields than the previously reported route for the synthesis of 4-cyano-4′-n-pentyl-d₁₁-biphenyl and also eliminates the main “impurity” present in the final product. The synthesis of 4-cyano-4′-n-pentyl-d₁₁-2′,3′,5′,6′-tetradeuteriobiphenyl is also reported.     

Synthesis,Crystal Structure and Characterization of (Z)-2-N′-hydroxyisonicotinamidine

The compound (Z)-2-N′-hydroxyisonicotinamidine, (2) was synthesized and characterized by ¹H NMR, FT-IR, FAB-Mass, UV-Visible Spectra, and elemental Analysis. Its molecular structure was solved by single crystal X-ray diffraction method. The title molecule, C₆H₇N₃O is crystallized in the orthorhombic crystal system with the space group Pna2₁ and with unit cell parameters a = 12.5664(8) Å, b = 8.8622(6) Å, c = 5.7953(4) Å, α = 90°, β = 90°, γ = 90°, and Z = 4. The molecular and crystal structure of the title molecule is stabilized by an intramolecular interaction of the type N—H···O, and the intermolecular interactions of types N—H···N and O—H···N.     

Synthesis and crystal structure of 1,1′-di(ethylpropionato)-2,2′-biimidazole, a macromolecular precursor

1,1,-Di(ethylpropionato)-2,2-biimidazole, C₁₆H₂₂N₄O₄, crystallizes from ice-cold ethanol in the space group P , with a = 4.6742(9), b = 9.1119(13), c = 10.175(2) Å, = 96.22(1), = 96.29(2), = 97.53(1)°, and Z = 1. The molecule crystallizes with coplanar rings and the substituents assume a trans conformation with a center of inversion between the bridging carbon atoms.     

Synthesis and Crystal Structure of Nitrogen-rich Compound: 2,5,2′-triazido-1,1′-azo-1,3,4-triazole

Abstract  The title compound 2,5,2′-triazido-1,1′-azo-1,3,4-triazole(2) has been synthesized by the reaction of 2,5,2′-trichloro-1,1′-azo-1,3,4-triazole(1) with sodium azide. Its crystal structure was determined by single-crystal X-ray diffraction. It crystallizes in triclinic, space group P−1 with a = 6.6604(13) ?, b = 6.7035(13) ?, c = 12.916 (3) ?, α = 98.13(3)°, β = 95.56(3)°, γ = 106.48° V = 541.68(18) ?³, Z = 2, C₄HN₁₇, Mr = 287.22, D _c  = 1.761 g cm⁻³, F(000) = 288 and μ(MoKa) = 0.140 mm⁻¹, the final R = 0.0553 and wR = 0.1541. X-ray analysis indicates a stronger delocalization of the azo π bond along the hypothetical N₄ moiety within the title compound than those in(E)-1,2-bis(2,6-diazido-9- azabicyclo[3.3.1]nonan-9-yl)diazene. Index abstract  The title compound 2,5,2′-triazido-1,1′-azo-1,3,4-triazole has been synthesized by the reaction of 2,5,2′-trichloro-1,1′-azo-1,3,4-triazole with sodium azide. Its crystal structure was determined by single-crystal X-ray diffraction. X-ray analysis indicates a stronger delocalization of the azo π bond along the hypothetical N4 moiety within the title compound than those in(E)-1,2-bis(2,6-diazido-9-azabicyclo[3.3.1] nonan-9-yl)diazene.      

The Preparation and Properties of the α,ω-bis(4,4′-Cyanobiphenyloxy)Alkanes: Nematogenic Molecules with a Flexible Core

The first twelve members of the homologous series of α,ω-bis(4,4′-cyanobiphenyloxy) alkanes have been synthesised. The compounds are nematogenic, although the mesophases for the first and third members of the series are monotropic. Both the nematic-isotropic transition temperature and the entropy of transition exhibit a pronounced dependence on the length of the flexible core; this is analogous to that found for main chain thermotropic liquid crystal polymers.     

Synthesis and X-ray structure of 5′-methoxy-2,4,6-trimethyl-2′-nitrosobiphenyl

The synthesis and X-ray crystal structure of 5-methoxy-2,4,6-trimethyl-2-nitrosobiphenyl is reported. The compound (C₁₆H₁₇NO₂) is monoclinic, with a = 11.080(4), b = 16.899(6), c = 15.410(5) Å, = 108.329(5)°, and space group P2₁/n. There are two independent molecules within the crystal. In each of these molecules the two phenyl rings are mutually orthogonal, with interplanar dihedral angles of 85.09 and 89.43° respectively. The nitroso substituents are essentially coplanar with the phenyl ring, with torsional angles of only 3.5 and 2.2°, respectively, while the methoxy groups make angles of 5.2 and 10.0°, respectively, with the phenyl ring.     

Synthesis,Characterization and Structural Conformation Studies of 2-Amino-3-ethoxycarbonyl-4-(4′-methoxy Phenyl)-4H-pyrano-[3,2-c]-chromene-6-methyl-5-one

2-amino-3-ethoxycarbonyl-4-(4′-methoxy Phenyl)-4H-pyrano-[3,2-c]-chromene-6-methyl-5-one was synthesized by the two-component reaction of 6-methyl-4-hydroxy coumarin with 4′-methoxy-2-cyano cinnamate, which was synthesized by Knoevenagel reaction with 88% yield. The compound obtained was characterized by spectroscopic techniques and confirmed by X-ray crystallographic studies. The crystallographic data analysis reveals that the title compound crystallizes in the triclinic space group \(P\overline{1}\) with cell parameters a = 7.7750(8) Å, b = 9.0310(6) Å, c = 15.6120(17) Å, α = 77.249(7)°, β = 115.860(3)°, γ = 70.139(7)°, V = 1,003.0(16) Å³ for Z = 4. The structure has been solved by direct methods and refined to R1 = 0.0552 for 3,164 observed reflections with I > 2 σ(I). The pyran ring is in a flattened boat conformation. The carbonyl group is oriented in a -synperiplanar(cis) conformation.

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The electronic nature of the substituents and the structure of 4,4′-dipyridilium dications. The crystal structure of N,N′-di(carbethoxymethyl)-4,4′-dipyridilium diperchlorate

The crystal structure of N,N′-di(carbethoxymethyl)-4,4′-dipyridilium diperchlorate (I) C₁₈H₂₂Cl₂N₂O₁₂ at 293 K is determined by the X-ray diffraction technique. The crystals are monoclinic, a = 5.501(1) Å, b = 26.460(5) Å, c = 8.140(2) Å, β = 100.63(3)°, space group P2₁/n, Z = 2, 2271 reflections measured (2052 reflections unique), R ₁ = 0.062, and wR2 = 0.141 for 1161 reflections with F ≥ 4σ(F). The interaction between the lone-electron pair of the carbonyl oxygen atom of the electron-withdrawing ester group and the π system of the dication manifests itself as the intramolecular O(1)?N contact (2.780 Å). In the absence of charge transfer from the counterion to the dication, this interaction contributes to the stabilization of a planar structure of the dication fragment of the molecule despite the electron-withdrawing nature of the ester groups.     

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)°.      

Synthesis, Characterization, and Crystal Structures of 3-bromo-N′-(2-methoxybenzylidene)benzohydrazide and N′-(2-methoxybenzylidene)-3,4-methylenedioxybenzohydrazide

Abstract  

Two new hydrazone compounds, 3-bromo-N′-(2-methoxybenzylidene)benzohydrazide (1) and N′-(2-methoxybenzylidene)-3,4-methylenedioxybenzohydrazide (2), have been synthesized and characterized by elemental analysis, IR, and single crystal X-ray diffractions. Compound (1) crystallizes in the triclinic space group P1 with unit cell dimensions a = 8.4088(5) ?, b = 8.5398(5) ?, c = 10.6572(6) ?, α = 90.356(3)°, β = 102.868(3)°, γ = 97.987(3)°, V = 738.28(7) Ǻ³, Z = 2, R ₁ = 0.0406, and wR ₂ = 0.0804. Compound (2) crystallizes in the tetragonal space group P4₁ with unit cell dimensions a = b = 9.792(4) ?, c = 15.788(6) ?, V = 1513.8(10) Ǻ³, Z = 4, R ₁ = 0.0415, and wR ₂ = 0.0818. The molecules of both compounds display E configurations with respect to the C=N double bonds. In the crystal structure of (1), molecules are linked through N–H···O hydrogen bonds, forming chains running along the b axis. In the crystal structure of (2), molecules are linked through N–H···O hydrogen bonds, forming chains running along the c axis.     

Syntheses,Structures and Optical Properties of a Series of Lanthanide Complexes with Chelidamic Acid and 4,4′-Bipyridyl

Abstract  

The title complexes, (C₁₀H₈N₂)·[Y(C₇H₃NO₅)(C₇H₄NO₅)·2H₂O]·3H₂O (1), (C₁₀H₈N₂)·[Er(C₇H₃NO₅)(C₇H₄NO₅)·2H₂O]·3H₂O (2), (C₁₀H₈N₂)·[La(C₇H₃NO₅)(C₇H₄NO₅)·2H₂O]·4.5H₂O (3), (C₁₀H₈N₂)·[Sm(C₇H₃NO₅)(C₇H₄NO₅)·2H₂O]·4.75H₂O (4), (C₁₀H₈N₂)·[Pr(C₇H₃NO₅)(C₇H₄NO₅)·2H₂O]·4.75H₂O (5) were synthesized and characterized by X-ray single-crystal diffraction. The crystal structures of 1–2 reveal that they are isomorphous, among which the metal atoms are all eight-coordinate with a distorted dodecahedron coordination geometry. The structures of 3–5 are isomorphic, among which the metal atoms are all nine-coordinate with distorted tricapped trigonal prismatic coordination geometries by two chelidamic acid ligands. Complexes 1–5 are formed into 3D networks by H-bonds. The optical properties of 1–5 were investigated in terms of fluorescent spectra, which all exhibit strong luminescence.     

Synthesis and crystal structure of 7-ethoxyl-4′-hydroxyisoflavone

7-Ethoxyl-4-hydroxyisoflavone was prepared and its crystal structure was examined by X-ray diffraction. Crystallization of the title compound occurs in the monoclinic, space group P2(1)/c with a = 11.144(2) Å, b = 10.209(1) Å, c = 13.191(2) Å, = 113.43(1) and Z = 4. The molecular structure of title compound consists of a benzopyranone moiety, a phenyl moiety, a hydroxyl and an ethoxyl group. The benzopyranone ring is not coplanar with the phenyl ring, the dihedral angle being 46.75. The ethoxyl group is nearly coplanar with its corresponding ring with the torsion angle 175.23(2). Three kinds of hydrogen bond and two kinds of aromatic stacking interaction link the title compounds into a three-dimensional networking structure.     

Elastic and Optical Properties of Some 4′-n-Alkyl-4-Cyanobiphenyls

The bend elastic constants (k ₃₃) and order parameters (S) derived from optical measurements in the nematic phase of pentlyl, hexyl, heptyl and octyl cyanobiphenyls (5CB, 6CB, 7CB and 8CB respectively) are reported. The odd-even effect is clearly seen in the K ₃₃ values of all four compounds and in the S values of the first three. 5CB, 6CB and 7CB show only the nematic mesophase but their elastic constants indicate the existence of smectic-like short range order. For example, even the lowest homologue, 5CB, does not obey the law k ₃₃ ∞ S ² given by the mean field throry. 7CB, has about the same order parameter as 5CB but a much higher elastic constant. 8CB, which shows a smectic A phase as well, exhibits a lower k ₃₃ than 7CB near the nematic-isotropic transition point but a pronounced pretransitional increase near the A-N transition.