Synthesis and Crystal Structure of N-（2-（1,3,4-oxadiazol-2-yl）phenyl）-2,3-dimethylaniline

The title compound, N-（2-（1,3,4-oxadiazol-2-yl）phenyl）-2,3-dimethylaniline, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, ^1H- and ^13C-NMR spectroscopy, elemental analysis and mass spectrometry. These experimental studies were supported by theoretical optimizations.     

Synthesis and Crystal Structure of （Z）-1- （3-Fluorobenzyl）-5-（（3-fluorobenzylimino）（2-hydroxy-4-methoxyphenyl）methyl）pyridin-2（1H）-one

The title compound （Z）-1-（3-fluorobenzyl）-5-（（3-fluorobenzylimino）（2-hydroxy-4- methoxyphenyl）methyl）pyridin-2（1H）-one （C27H22F2N2O3,Mr = 460.47） was synthesized and crystallized. The crystal belongs to the triclinic system,space group P1 with a = 9.951（6）,b = 10.059（6）,c = 12.927（7）A,α = 109.828（7）,β = 102.304（7）,γ = 104.898（7）°,Z = 2,V = 1110.2（11）A^3,Dc =1.377 Mg/m^3,μ（MoKα） = 0.102 mm^-1,F（000） = 480,the final R = 0.0449 and Rw = 0.1250 for 4595 observed reflections （I 〉 2σ（I））. X-ray analysis reveals that both m-fluorobenzyl groups are diorientationally disordered because of the rotation of C–C single bond which was represented as F（1）,F（2） and F（1＇）,F（2＇）. The diorientational disorder was refined and gave the occupancies of 0.665（4） and 0.335（4） for F（1） and F（1＇）,0.631（3） and 0.369（3） for F（2） and F（2＇）. Hydrogen bonds existing in the cell link different components to stabilize the crystal structure. The active data proved that the title compound has good anti-HBV activity.     

Simultaneous spectrophotometric determination of cobalt,copper and nickel using 1-（2-thiazolylazo）-2-naphthol by chemometrics methods

The simultaneous determination of cobalt, copper and nickel using 1-（2-thiazolylazo）-2-naphthol （first figure of this article） by spectrophotometric method is a difficult problem in analytical chemistry, due to spectral interferences. By multivariate calibration methods, such as partial least squares （PLS） regression, it is possible to obtain a model adjusted to the concentration values of the mixtures used in the calibration range. Orthogonal signal correction （OSC） is a preprocessing technique used for removing the information unrelated to the target variables based on constrained principal component analysis. OSC is a suitable preprocessing method for PLS calibration of mixtures without loss of prediction capacity using spectrophotometric method. In this study, the calibration model is based on absorption spectra in the 550-750-nm range for 21 different mixtures of cobalt, copper and nickel. Calibration matrices were formed from samples containing 0.05-1.05, 0.05-1.30 and 0.05-0.80 μg·mL^-1 for cobalt, copper and nickel, respectively. The root mean square error of prediction （RMSEP） for cobalt, copper and nickel with OSC and without OSC were 0.007, 0.008, 0.011 and 0.031,0.037, 0.032 μg· mL^-1, respectively. This procedure allows the simultaneous determination of cobalt, copper and nickel in synthetic and real samples and good reliability of the determination was proved.     

Ferroelectricity based on coordination compound： Transition metal Co（Ⅱ） sulfates templated by homochiral 2-methylpiperazine （C5H14N2）[ Co（H2O）6]（SO4）2

Reacting homochiral （R）-2-methylpiperazine with cobalt sulfate heptahydrate by the solution method in the presence of concentrated sulfuric acid （H2SO4） yielded two coordination compounds （C5H14N2） [CO（H2O）6]（SO4）2 （1 and 2）. They are polymorphs, but their hydrogen bonds structure differ significantly. Both 1 and 2 crystallize in chiral space group P21 which is related with point group C2, and experimental results suggest that 1 displays ferroelectric behaviors.     

One-pot synthesis of 2-（1-acyloxypentyl） benzoic acids

A one-pot synthesis of 2-（1-acyloxypcntyl） benzoic acids by trapping the carboxylatc/alkoxide dianion with acylating reagents following Grignard addition with n-BuMgBr to 2-formylbcnzoic acid was described. Compared with routine synthetic method, this novel procedure has the advantage of convenient operation and higher yields.     

Quantum Chemistry Studies on the Fe-Cu Interactions and 31p NMR in Fe（CO）3（Ph2Ppy）2（CuXn） （Xn = Cl2^2-, Cl-, Br-）

In order to study the Fe-Cu interactions and their effects on 31p NMR, the structures of mononuclear complex Fe（CO）3fPhzPpy）a 1 and binuclear complexes Fe（CO）3（PhEPpy）z（CuXn） （2： Xn = Cl2^2-, 3： Xn = Cl-, 4： Xn = Br-） are calculated by density functional theory （DFT） PBE0 method. For complexes 1, 3 and 4, the 31p NMR chemical shifts calculated by PBE0-GIAO method are in good agreement with experimental results. The 31p chemical shift is 82.10 ppm in the designed complex 2. The Fe-Cu interactions （including Fe→Cu and Fe←Cu charge transfer） mainly exhibit the indirect interactions. Moreover, the Fe-Cu（I） interactions （mostly acting as σFe-p→4Scu and aFe-C→4Scu charge transfer） in complexes 3 and 4 are stronger than Fe-Cu（Ⅱ） interactions （mostly acting as σFe-p→4Scu and σFe-p←4Sc,） in complex 2. In complex 2, the stronger Fe←Cu interac- tions, acting as σFe-p←44SCu charge transfer, increase the electron density on P nucleus, which causes the upfield 31p chemical shift compared with mononuclear complex 1. For 3 and 4, although a little deshielding for P nucleus is derived from the delocalization of σFe-p→4Scu due to the Fe→Cu interactions, the stronger σFe-c→np charge-transfer finally increases the electron density on P nucleus. As a result, an upfield 31p chemical shift is observed compared with 1. The stability follows the order of 2〉3=4, indicating that Fe（CO）3（PhzPpy）2（CuCl2） is stable and could be synthesized experimentally. The N-Cu（Ⅱ） interaction plays an important role in the stability of 2. Because the delocalization of σFe-p→4SCu and σFe-c→πc-o weakens the a bonds of Fe-C and ~r bonds of CO, it is favorable for increasing the catalytic activity of binuclear complexes. Complexes 3 and 4 are expected to show higher catalytic activity compared to 2.     

Crystal Structure and Biological Activities of N-（5-（4-Chloro-2-（trifluoromethyl）phenyl）furan-2-carbonyl）-N＇-（4,6,dimethylpyrimidin-2-yl）thiourea

The new title compound N-（5-（4-chloro-2-（trifluoromethyl）phenyl）furan-2-carbon-yl）- N＇-（4,6-dimethylpyrimidin-2-yl）thiourea （C19H14C1F3N4O2S） has been synthesized, and its crystal structure and biological behaviors were studied. The title compound crystallizes in the monoclinic system, space group P21/c with a = 7.932（5）, b = 33.46（2）, c = 7.556（5） A, β = 98.058（9）°, V = 1986（2） A^3 Mr = 454.85, Z = 4, Dc = 1.521 g/cm^3, μ = 0.349 mm^-1 and F（000） = 928. The structure was solved by direct methods and refined to R = 0.0724 and wR= 0.1429 for 3494 observed reflections （I 〉 2σ（I））. Intermolecular hydrogen bonds along the b axis together with the continuous π-π interactions construct the three-dimensional architecture of the title compound. The preliminary biological tests show definite herbicidalactivity for the title compound.     

Theoretical Study on the Stable Structures and Aromaticities for Pnictogen Dianionic Sb4^2-, Bi4^2-, and （SbBi）2^2- Clusters

Through the theoretical calculation of structural optimization, vibrational frequencies and atomization energies with one method of density functional theory （B3LYP） and two post- Hartree-Fock approaches （MP2, CCSD（T））, several stable isomers for new three pnictogen dianionic Sb4^2-, Bi4^2-, and （SbBi）2^2- species were determined. For two homoatomic Sb4^2- and Bi4^2- species, there are three stable isomers： square （D4h）, roof-shaped （C2v-1）, and C2v-2 structure with the square isomer being the ground state. For the heteroatomic dian- ionic （SbBi）2^2- species, there are also three stable isomers： rhombus （D2h）, roof-shaped （C1）, and C2v structures with the rhombic isomer being the ground state. The calculated NICS values show that nucleus-independent chemical shifts （NICS） values of roof-shaped isomers for Sb4^2-, Bi4^2-, and （SbBi）2^2- species are all negative, consequently indicating that these roof-shaped isomers possess aromaticities. NICS values for the planar ring isomers are all positive, suggesting that these three planar ring isomers have antiaromatic characters. The aromaticity for the two stable roof-shaped and square isomers are preliminarily explained and discussed with MO analysis.     

Synthesis and Crystal Structure of （E）-4- （Benzyloxy）-2-（cinnamoyloxy）-N,N,N-trimethyl-4- oxobutan-l-aminium Chloride as a Double-prodrug

A novel hydrochloride quaternary ammonium salt （E）-4-（benzyloxy）-2-（cinnamo- yloxy）-N,N,N-trimethyl-4-oxobutan-l-aminium chloride （Cz3HzgNO4Cl2, Mr = 454.37） has been synthesized via the sequence of acetylation and esterification by using L-carnitine （L-4-N-trimethy- lammonium-3-hydroxybutyric acid, LC） and cinnamic acid as the starting materials, and its crystal structure was determined by single-crystal X-ray diffraction method. The crystal belongs to monoclinic, space group P212121 with a = 10.1670（4）, b = 10.4488（4）, c = 22.9795（11）A, V = 2441.18（18）A3, Z = 4, Dc = 1.236 g/cm3,μ（MoKa） = 0.293 mm-1, F（000） = 960, Flack factor = -0.01（11）, the final R = 0.0489 and wR = 0.1550 for 3350 observed reflections （I 〉 2σ（/）） and R = 0.0953 for all 5648 unique reflections. The crystal structure involves a conjugated system which shows a reverse olefin structure.     

Synthesis,Crystal Structure,Characterizationand Quantum Chemical Studies on 1N-Acetyl-3-（2,4-dichloro-5-fluorophenyl）-5-（p-methyl-phenyl）-2-pyrazoline

1N-Acetyl-3-（2,4-dichloro-5-fluoro-phenyl）-5-（p-methyl-phenyl）-2-pyrazoline has been synthesized and characterized by elemental analysis, IR, UV-Vis and X-ray single-crystal diffraction. Ab intio calculations have been carded out for the compound by using both B3LYP and HF methods at the 6-31G^＊ basis set. The calculated results show that the predicted geometry can well reproduce the structural parameters. The electronic absorption spectra calculated by B3LYP/6-31G^＊ method are approximate to the experiments and the Natural Bond Orbital （NBO） analyses suggest that the above electronic transitions are mainly assigned to n→π^＊ and π→π^＊ transitions. CIS-HF/6-31G^＊ method is not suitable to predict the electronic spectra for the title compound. The calculation of the second order optical nonlinearity was carded out, giving the value of molecular hyperpolarizability equal to 2.194^＋ 10^-30 esu. On the basis of vibrational analyses, the thermodynamic properties of the compound at different temperature have been calculated, revealing the correlation between C p, m^0, S m^0, H m^0 and temperature.     

One Pot,Multi-component Synthesis of 3-[（4-Aryl-thiazol-2-yl）-hydrazono]-1,3-dihydro-indole-2-one

A series of 3-[（4-phenyl-thiazol-2-yl）-hydrazono]-1,3-dihydro-indole-2-one（4a-4g） and 3-{[4-（2-oxo2H-chromen-3-yl）-thiazol-2-yl]-hydrazono}-1,3-dihydro-indol-2-one（6a-6d） has been prepared in a one-step procedure from condensation reaction of isatin（1）,thiosemicarbazide（2） and bromoacetophenones（3）/or 3-（2-bromoacetyl）coumarins（4）.The method provides a simple and efficient route to prepare the compounds in good yields and in a short experimental time as compared to its stepwise procedure.     

3-N-丙酰基-2-芳基-5-(2-碘苯基)-1,3,4-噁唑啉类化合物的合成

2-碘苯甲酰肼与芳醛反应得到相应的酰腙(1),1再与丙酸酐脱水环化合成了3-N-丙酰基-2-芳基-5-(2-碘苯基)-1,3,4-噁唑啉类化合物,其结构经1H NMR,IR,MS和元素分析表征。     

金属串配合物[Ni3(L)4(NCS)2](L = dpa-, mpta-, mdpa-, mppa-)结构和磁性的理论研究

应用密度泛函理论BP86方法结合自然键轨道分析方法对具有分子导线潜在应用前景的金属串配合物[Ni₃(L)₄(NCS)₂](L = dpa^- (1), mpta^- (2), mdpa^- (3), mppa^- (4))进行研究,分析了桥联配体L对Ni―Ni相互作用和磁耦合性质的影响.结果得到: (1)配合物的基态均是对应于五重态(HS)的反铁磁(AF)单重态, HS的能量和结构与AF态相近, Ni₃⁶⁺链形成了三中心四电子σ键(σ₂σ_nb¹σ^*1). (2) dpa^-引入甲基成为mdpa^-,对Ni―Ni、Ni―N距离影响不大; 3H-吡咯环和噻唑环取代吡啶环后, N1―N2、Ni―Ni距离增大, Ni2―N2键长缩短,但噻唑环的影响较小;故Ni―Ni相互作用强度为1 ≈ 3 > 2 > 4. (3)预测了3和4的J_ab值为-103和-88 cm^-1,随Ni―Ni相互作用增强磁耦合效应增大. Ni―Ni相互作用越大,通过Ni₃⁶⁺链σ型轨道的直接磁耦合越强; Ni2―N2键越强,通过涉及桥联配体的间接磁耦合越强,直接磁耦合比间接磁耦合更强.     

N-(取代苯基)-2-(对氯苯氧乙酰基)氨基脲的合成与表征

以无机碱为催化剂，用不同的Ｎ－（聚代基）三氯乙酰胺与对氯苯氧乙酰肼反应，首次合成了３种新的取代氨基基脲化合物Ｎ－（取代苯基）－２－（对氯苯氧乙酰基）氨基脲，产率７１％以上。     

Synthesis and aromatization of 2-(3,6-diaryl-2,5-dihydropyridazin-4-yl)-1H-benzimidazoles

Treatment of 1,4-diaryl-2-(1H-benzimidazol-2-yl)butane-1,4-diones with hydrazine gives the previously unknown 2-(3,6-diaryl-2,5-dihydropyridazin-4-yl)-1H-benzimidazoles which are aromatized by oxidation with nitrous acid to give 2-[3,6-diarylpyridazin-4-yl]-1H-benzimidazoles. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 252–259, February, 2008.     

Synthesis,studies and in vitro antibacterial activity of some 5-(thiophene-2-yl)-phenyl pyrazoline derivatives

In the present investigation, a novel series of pyrazolines 2a–2d were synthesized by the cyclization of various -1-[2-(alkoxy) phenyl]-3-(thiophen-2-yl) prop-2-en-1-one 1a–1d with N-substituted phenyl hydrazine and thiosemicarbazide in the presence of CH₃COOH and NaOH in ethanol which lead to the formation of new pyrazolines. The structures of these compounds were elucidated by, IR, ¹H-NMR, ¹³C-NMR, ESI-MS spectral data and their purities were confirmed by elemental analyes. The in vitro antibacterial activity of these compounds was evaluated against two Gram-positive and two Gram-negative bacteria Aeromonas hydrophila, Yersinia enterocolitica, Listeria monocytogenes, and Staphylococcus aureus by microdilution method and then the minimum inhibitory concentration (MIC) of these compounds was determined. The results showed that compounds 1-[2-(benzyloxy) phenyl]-5-(thiophen-2-yl)-1-phenyl-4,5-dihydro-1H-pyrazol-4-yl (2b) and 1-[2-(naphthalen-2-ylmethoxy) phenyl]-5-(thiophene-2-yl)-1-phenyl-4,5-dihydro-1H-pyrazole-4-yl (2d) showed most promising antibacterial activity as compared to the antibiotics gentamicin and tetracycline in (Table 1, Table 2).     

Synthesis of 2-Alkyl（aryl）-3-methylthio-6-methyl-6-arylpyrano-[4, 3-c]pyrazol-4（2H）-ones

The synthesis of 2-alkyl(aryl)-3-methylthiopyrano[4,3-c]pyrazol-4(2H)-ones via 5, 6-dihydro-2H-pyran-2, 4-dione-3-dithioacetals with (un)substituted hydrazines is described and the mechanism of the formation of title compounds is discussed. Their structures were confirmed by ^1HNMR spectra and elemental analysis.     

Synthesis and Herbicidal Activities of Potassium Methyl 1-(Substituted Phenoxyacetoxy)alkylphosphonate

A series of potassium methyl 1-(substituted phenoxyacetoxy)alkylphosphonates(9a―9o) was designed and synthesized. The results of preliminary bioassays indicate that most of the title compounds possess excellent pre-emergence and post-emergence herbicidal activities against Brassica napus, Amaranthus mangostanus, Medicago sativa, Echinochloa crusgalli, and Digitaria sanguinalis at a dosage of 1500 g/ha(1 ha=10000 m²). Especially, potassium methyl 1-(2,4-dichlorophenoxyacetoxy)-1-(4-methylphenyl)methylphosphonate(9g) and potassium methyl 1-(2,4-dichlorophenoxyacetoxy)-1-(furan-2-yl)methylphosphonate(9j) show the best herbicidal activity against five tested weeds with more than 85% inhibitory rate in pre-emergence.     

Synthesis,Crystal Structure and Theoretically Study of 2-(Dimethylamino)-1,3-dithiocyanatopropane and Its Isomer

2-(Dimethylamino)-1,3-dithiocyanatopropane(1) has been prepared as a key intermediate synthesizing a natural insecticide Cartap by the reaction of 1-dimethylamino-2,3-dichloropropane with sodium thiocyanate. The crystal structures of compound 1 and its isomer 1-(dimethylamino)-2,3-dithiocyanotopropane(2) formed during the reaction were determined by X-ray single-crystal diffraction. Bond lengths in both the compounds are common and fall within normal ranges. There are some weak C―H×××N hydrogen bonds in the lattice of compound 1, which makes it form a three-dimensional network, which stabilize the crystal structure. No classic hydrogen bonds were founded in its isomer(2), only van der Waals forces contribute to the stability of the structure. In addition, DFT and MP2 calculations with 6-311+G(d, p) basis set have also been carried out to investigate the thermodynamic properties of compounds 1 and 2. The research will be applied to the further investigation of the tautomerization of compounds 1 and 2.     

The Synthesis of 2-(5-(Aryloxymethyl)-1,3,4-thiadiazol-2-ylthio)-N-arylacetamides at Room Temperature via Grinding

Fifteen 2-(5-(aryloxymethyl)-1,3,4-thiadiazol-2-ylthio)-N-arylacetamides were efficiently synthesized from the reaction of 2-chloro-N-arylacetamide with 5-(aryloxymethyl)-1,3,4-thiadiazole-2-thiol under solvent-free conditions at room temperature via grinding. The key advantages of the method are the short reaction time, high yields, simple workup, and environmentally friendly conditions compared to conventional heating.