Chiral recognition in the crystal structure of a dichiral mesogen with a unique isotropic mesophase: 2-{4-[(R)-2-fluorohexyloxy]phenyl}-5-{4-[(S)-2-fluoro-2-methyldecanoyloxy]phenyl}pyrimidine

The crystal structure of the title compound, which has an optically isotropic IsoX phase with an endothermic transition on cooling from an Sm*C phase, has been determined at 230 K. The crystal has a smectic-like layer structure composed of four crystallographically independent molecules. In the layer, one-dimensional chains of tightly fitted pyrimidine rings, with N... H distances shorter than the van der Waals radii, result in the large overlapping of core moieties and further induce close contacts and stereo-specific F-methyl interactions between the chiral groups; this is considered to be responsible for the uniquely organized IsoX phase.     

Synthesis and Crystal Structure of Tert-butyl 4-[(E)-4-(1,3 -Dioxo-1,3-dihydro-2H-isoindol-2-yl)-1-butenyl] Benzoate

1 INTRODUCTION Phthalimide and its derivatives are synthetic mate- rials, which are widely used as important chemical intermediates of biosensors[1] and many drugs such as Citalopran[2], luminal[3], Beta-Lactam[4] and the No. three generation quinolones[5], and they have been identified as active groups of some drugs and chemical luminescence reagents[6, 7]. Tert-butyl 4- [(E)-4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-1- butenyl] benzoate is an intermediate of a new type of insulin sen…     

Synthesis, spectroscopic characterizations and quantum chemical computational studies of (Z)-4-[(E)-(4-fluorophenyl)diazenyl]-6-[(3-hydroxypropylamino)methylene]-2-methoxycyclohexa-2,4-dienone

In this study, the molecular structure and spectroscopic properties of the title compound were characterized by X-ray diffraction, FT-IR and UV-vis spectroscopies. These properties were also investigated using DFT method. The most convenient conformation of title compound was firstly determined. The geometry optimizations in gas phase and solvent media were performed by DFT methods with B3LYP adding 6-31G(d) basis set. The differences between crystal and computational structures are due to crystal packing in which hydrogen bonds play an important role. UV-vis spectra were recorded in different organic solvents. The results show that title compound exists in both keto and enol forms in DMSO, EtOH but it tends to shift towards enol form in benzene. The polar solvents facilitate the proton transfer by decreasing the activation energy needed for Transition State. The formation of both keto and enol forms in DMSO and EtOH is due to decrease in the activation energy. TD-DFT calculations starting from optimized geometry were carried out in both gas and solution phases to calculate excitation energies of the title compound. The non-linear optical properties were computed at the theory level and the title compound showed a good second order non-linear optical property. In addition, thermodynamic properties were obtained in the range of 100-500K.     

Synthesis and Crystal Structure of 4-[（1E）-（4-Hydroxy-3,5-dimethoxybenzylidene）-amino]-1,5-dimethyl-2-phenyl-2,3-dihydro-1H-pyrazol-3-one

The title compound (C20H21N3O4, Mr = 367.40) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction. The crystal is of orthorhombic, space group P212121 with a = 7.5143(15), b = 13.901(3), c = 18.545(4) , V = 1937.1(7) 3, Z = 4, Dc = 1.260 g/cm3, μ = 0.089 mm-1, F(000) = 776, the final R = 0.0616 and wR = 0.0912. X-ray diffraction reveals that the molecule adopts an E configuration about the central C=N double bond. The intermolecular O–H…O hydrogen bond stabilizes the crystal structure by causing the formation of a supramolecular architecture.     

Crystal Structure of 2-[(N-methyl-N-phenyl ) aminomethyl] flavanone

1INTRODUCTIONSyntheticflavone(2-phenyl-benzopyran-4-one)anditsderivativeshaveattractedconsider-ableattentionfortheyareimportantnaturalcompoundshavingwidebiologicalandphysio-logicalactivities[1i.Recently,oninvestigatingthereactionofflavone(FL)withN,N-dimethylaniline(DMA)underphotoinducedconditioninbenzene,weobtainedanFL-DMAadditionproduct,thetitlecompound1,whichisanewderivativeofflavoneanddif-ficultlysynthesizedbythermalmethodt2i-Here,wereportitsX-raycrystalstruc-ture.2EXPER1MENTA…     

Synthesis and Crystal Structure of 2-[（2-Chloropyridin-4-yl）oxy]-3,3-diphenyl-3-methoxypropionic Acid

The title compound was synthesized and its crystal structure was determined by single-crystal X-ray diffraction.The crystal is of orthorhombic system(C21H18ClNO4,Mr = 383.81),space group Pca21 with a = 13.913(3),b = 10.273(2),c = 26.488(5),V = 3786.1(13) 3,Z = 8,Dc = 1.347 g/cm3,F(000) = 1600,μ = 0.228 mm-1,the final R = 0.0550 and wR = 0.1278 for 5065 observed reflections(I > 2σ(I)).The title compound in a racemic form was found to exist as a mixture of two enantiomers in an equal ratio in the unit cell.The intermolecular hydrogen bonds link the molecules in a head-to-end manner to generate an infinite chain.     

Synthesis, Crystal Structure and Antibacterial Activities of 3-[（2-Hydroxy-4-diethylamino-phenyl）methylenehydrazinocarbonyl]-4-hydroxy-6-methyl-2（1H）-pyridinones

1 INTRODUCTION Recently, compounds containing pyrazole, imida- zole, triazole (including benzotriazole), pyridine, tetrazole and indole have attracted much interest because of their fungicidal activity, plant-growth regulating activity and antibacterial activity[1～3]. Schiff bases also constitute a good type of biolo- gically active substructures[4～7]. Studies of pyri- dine Schiff base-type fungicides have been repor- ted[8]. However, some structures of pyridine com- pounds containing h…     

Crystal structure of 4,4-bipyridine-containing complexes of copper(II) nitrate with 1-[(2-Hydroxyethylimino)methyl]naphthalen-2-ol and 2-[(2-hydroxyethylimino)methyl]phenol

The crystal structures of (μ-4,4-bipyridine)-di(nitrato-1-[(2-hydroxyethylimino)methyl]naphthalen-2-olocopper (I) and catena-di(μ-4,4’-bipyridine)di(μ-4,4’-bipyridine)-di(nitrato-2-[2-(hydroxyethylimino) methyl]phenolocopper)diaquacopper(II) nitrate (II) were determined. In the crystal of I, each of the two copper atoms coordinates a singly deprotonated tridentate azomethine molecule, a nitrate ion, and bipyridine, which functions as a bridge between the central atoms. The copper coordination polyhedron is a slightly distorted tetragonal pyramid with the base formed by the imine and bipyridine nitrogen atoms and the phenol and alcohol oxygen atoms. The axial site in the pyramid is occupied by the oxygen atom of the monodentate nitrate groups. In the trinuclear structure II with C₂ crystal chemical symmetry, the terminal coordination unit is composed through copper coordination of monodeprotonated 2-[2-(hydroxyethylimino)methyl]phenol, bipyridine, and the nitrate anion. In the crystal, the trinuclear molecules form infinite ribbons along the z axis in which the pyridine molecules perform the bridging function. The central copper atom has an octahedral configuration formed by the nitrogen atoms of four 4,4’-bipyridine molecules and oxygen of two water molecules.     

有机配体Schiff碱4-(2-羟基苯基)-亚氨基-戊-2-酮的从头算研究

本文通过从头算HF／6－31G（d）方法,对Schiff4－（2－羟基苯基）－亚氨基－戊－2－酮 进行了理论研究,提供了该化合物两种互变异构体的几何构型参数、电子结构、IR光谱性 、偶极矩数据,并借助热、动力学手段,分析了两种互变异构体的异构平衡过程。计算结果表明：（1）从几何构型、电子 结构和相对能量的角度考虑,由于较强的分子内氢键作用和较大的共轭体系,亚胺烯醇式更为稳定。（2）从分子极性的角度考虑,烯胺酮式具有较大的偶极矩,其较强的分子间作用力有利形成晶体,因而烯胺酮式以晶体的形式存在。（3）由烯胺酮式向亚胺烯醇式转化的互变异构反应是热力学自发反应,但受到较大活化能的控制,是一个动力学稳定体系。分析了极性溶剂存在的互变异构反应是热力学自发反应,但受到较大活化能的控制,是一个动力学稳定体系。分析了极性溶剂存在将有利于反应发生且标题化合物以亚胺烯醇式存在于极性溶剂中的作用。以上结论均与实验研究结果相符。     

Direct electrochemical synthesis and crystal structure of the Zinc(II) Carbamato Complex {[N-methyl-N′-[(2-pyrrolyl)-methylene]ethylenediamine][N-methyl-N-[2-[(2-pyrrolato)-methyleneamino]ethyl]carbamato]}zinc(II)

The electrochemical oxidation of anodic zinc in an acetonitrile solution of a Schiff base derived from Hpyrrole-2-carbaldehyde and N-methylethylenediamine gives [Zn(C₈H₁₃N₃)?(C₉H₁₁N₃O₂)], whose crystal structure has been determined. The compound crystallizes in the orthorhombic space group P_bca (No. 61) with a = 13.757(2), b = 17.748(4), c = 14.808(4) Å and Z = 8. Refinement converged to R = 0.049 for 1407 independent observed reflections. The crystal structure consists of monomeric molecules in which the central ZnN₄O unit has distorted trigonal bipyramidal geometry and the carbamato group is monodentate.     

Crystal Structure of 3－［（α－Phenyl） triphenyl germylethyl］－4－phenyl－Δ~2－1，2，4－triazoline－5－thione

ＣｒｙｓｔａｌＳｔｒｕｃｔｕｒｅｏｆ３－［（α－Ｐｈｅｎｙｌ）ｔｒｉｐｈｅｎｙｌｇｅｒｍｙｌｅｔｈｙｌ］－４－ｐｈｅｎｙｌ－Δ~２－１，２，４－ｔｒｉａｚｏｌｉｎｅ－５－ｔｈｉｏｎｅＣｈｅｎＲｕ－Ｙｕ；ＬｉＦｅｎｇ－Ｆｕ（ＩｎｓｔｉｔｕｔｅｏｆＥｌｅ?..     

Crystal and Molecular Structure of Ethyl 2-[（4-Hydroxy-phenyl）hydrazono]-3-oxobutanoate

The title compound,C 12 N 2 O 4 H 14 (M r=250.3),crystallizes in triclinic P1 space group with a=7.7709(9),b=8.7534(11),c=9.6958(12),α=77.103(2),β=80.496(2),γ=86.726(2)o,V=633.9(1) 3,Z=2,F(000)=264,D c=1.311 Mg/m 3,μ(MoKα)=0.1 mm-1,the final R=0.056,and wR=0.15 for 2239 observed reflections (I > 2σ(Ⅰ)).The molecules in the crystal are linked through O-H···O type of hydrogen bonding interaction forming an infinite chainlike structure.The phenylhydrazone ring and oxobutanoate groups are almost planar.The keto hydrazo group adopts a Z-configuration in the molecule and the torsion angle is-177.6(2)°.     

2-氨基-3-氰基-4-芳基-6-二茂铁基吡啶的合成

以乙酰二茂铁、芳香醛、丙二腈为原料, 在乙酸铵存在下以乙醇为溶剂, 采用一锅煮的方法合成了8个2-氨基-3-氰基-4-芳基-6-二茂铁基吡啶化合物, 产率中等. 并通过X射线衍射分析确证产物4e的结构.     

Synthesis, Crystal Structure and Fungicidal Activity of (E)-2-[(4-tert-Butyl-5- (4-methoxybenzyl)thiazol-2-ylimino)methyl]phenol

The title compound(E)-2-(4-tert-butyl-5-(4-methoxybenzyl)thiazol-2-ylimino)me-thylphenol was synthesized by the reaction of 5-(4-methoxybenzyl)-4-tert-butylthiazol-2-amine with salicylaldehyde=and its crystal structure was determined by single-crystal X-ray diffraction.The crystal belongs to the monoclinic system=space group P21/c with a=5.9362(8)=b=11.5070(15)=c=29.460(4)=β=97.326(3)°=V=1995.9(5)3=Z=4=F(000)=808=C22H24N2O2S=Mr=380.49=Dc=1.266 g/cm3=S=1.031=μ=0.181 mm--1=the final R=0.0474 and wR=0.1441 for 4327 observed reflections(I > 2σ(I)).Intramolecular O-H…N hydrogen bond is observed in the crystal.The preliminary bioassay showed that the title compound exhibits 95% inhibition rate against Rhizoctonia solani at the test concentration of 500 mg/L.     

Structure determination of bis{(4Z)-1-(2-azidoethyl)-4-[(pyridin-2-yl)methylidene]-2-thiolatoimidazol-5(4H)-one}dicopper chloride from X-ray powder diffraction data

The new tridentate organic N₂S-type ligand, (4Z)-1-(2-azidoethyl)-4-[(pyridin-2-yl)-methylidene]-2-thioxoimidazol-5(4H)-one (LH), was synthesized. The reaction of LH with copper(II) chloride in a CH₂Cl₂/MeOH mixture afforded the coordination compound of the composition L₂Cu₂Cl (3). The crystal structure of 3 was solved and refined from X-ray powder diffraction data. Complex 3 has a binuclear structure with a short interatomic Cu-Cu distance and one bridging chlorine atom, which is located almost symmetrically with respect to both metal atoms. The planar organic ligands are noncoplanar and are at an angle of 53.56(1)° to each other.     

Synthesis and Crystal Structure of N-[4-(4-Methyl-phenylsulfamoyl)-phenyl]-4-methyl-1,2,3-thiadiazole-5-carboxamide

The crystal structure of the title compound (C17H16N4O3S2, Mr = 388.46) has been determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/c with a = 13.688(2), b = 16.704(3), c = 8.3308(12) , β = 99.474(6)o, V = 1878.8(5) 3, Mr = 388.46, Z = 4, Dc = 1.373 g/cm3, μ = 0.308 mm–1, F(000) = 808, R = 0.0389 and wR = 0.0917. X-ray analysis reveals that the crystal structure involves intermolecular N–H…O and N–H…N hydrogen bonds, which link the molecules into a layer parallel to the ac plane.     

Synthesis and Crystal Structure of 5-Methyl- 2-phenyl-4-[（2-p-bromophenylamino）-furylmethylene]-3（2H）-one

A novel 4-heterocyclic acylpyrazolone-based Schiff base compound 5-methyl- 2-phenyl-4-[（2-p-bromophenylamino）-furylmethylene]-3（2H）-one （C21H16N3O2Br） has been synthesized by the reaction of 1-phenyl-3-methyl-4-（α-furoyl）-pyrazolone-5 （HPMαFP） and p-bromoaniline. Elemental analysis, IR spectra and X-ray single-crystal diffraction were carded out to determine the composition and crystal structure of the compound. Crystal data： triclinic system, space group P1^-, a = 9.0936（3）, b = 9.8067（4）, c = 11.6863（4） A, α = 102.512（10）, β = 90.9630（10）, γ = 114.327（10）°, Mr= 422.28, Z= 2, F（000） = 428.0, V= 920.46（11）A^3, Dc = 1.524 g/cm^3,μ = 2.254mm^-1, R = 0.0476 and wR = 0.1318 for 9389 independent reflections （Rint = 0.0122） and 3281 observed reflections （I 〉 2σ（I））. Structural analysis indicates that the compound exists in an amine-one form.     

Vibrational study of (CH3)4NSbCl6 and [(CH3)4N]2SiF6

(CH3)4NSbCl6 and [(CH3)4N]2SiF6 are face-centred cubic compounds at ambient temperature with a = 11.548 and 11.172 A, respectively. The vibrational spectra of these two compounds are discussed in relation to their crystal structure and other compounds containing (CH3)4N+ ions. The assignment of the observed bands is discussed. The Raman and infrared spectra of [(CH3)4N]2SiF6 show that the cations and anions are not distorted inside the crystals and are weakly hydrogen-bonded to each other. The infrared spectrum of (CH3)4NSbCl6 confirms a cubic structure for this compound at ambient temperature, in which cations are in octahedral environments and can be interpreted as being disordered groups. No evidence could be found for the existence of hydrogen bonding between cations and anions in this compound. The phase transition of (CH3)4NSbCI6 is studied by means of Raman spectroscopy. It is believed to be governed by the reorientational motions of tetramethylammonium cations and may be classified as an 'order-disorder' type.     

Synthesis and Structure Characterization of N-Phenyl-（2S）-hydroxy-3-[（2-hydroxybenzylidene）amino]propionamide

1 INTRODUCTION Schiff bases can be conveniently prepared from the corresponding aldehyde and primary amine, which, as multidentate ligands, have already received great attention. Many metal complexes of this kind of ligands have been used successfully in various re- actions, such as Diels-Alder and hetero-Diels-Alder reactions[1], kinetic resolution of racemic epoxides[2], and Nozaki-Hiyama-Kishi (NHK) reaction[3]. Recen- tly Berkessel et al. have reported that the Cr- complex of sal…     

Synthesis and crystal structure of (E)-[(2-cyclohexenyl) vinyl]triaryltin

(E)-[(2-Cyclohexenyl)vinyl]triaryltin (aryl=phenyl, p-tolyl) were synthesized and characterized by elemental analysis, IR, 1H NMR spectroscopy. The crystal structure of (E)-[(2-cyclohexenyl)vinyl]triphenyltin was also determined by the X-ray diffraction. Experiments show that this compound has the conjugated system, which makes it have possible bioactivity and anti-tumor activity.