Synthesis,crystal structure and antifungal activity of a divalent cobalt(II) complex with uniconazole

Azole compounds have attracted commercial interest due to their high bactericidal and plant‐growth‐regulating activities. Uniconazole [or 1‐(4‐chlorophenyl)‐4,4‐dimethyl‐2‐(1H‐1,2,4‐triazol‐1‐yl)pent‐1‐en‐3‐ol] is a highly active 1,2,4‐triazole fungicide and plant‐growth regulator with low toxicity. The pharmacological and toxicological properties of many drugs are modified by the formation of their metal complexes. Therefore, there is much interest in exploiting the coordination chemistry of triazole pesticides and their potential application in agriculture. However, reports of complexes of uniconazole are rare. A new cobalt(II) complex of uniconazole, namely dichloridotetrakis[1‐(4‐chlorophenyl)‐4,4‐dimethyl‐2‐(1H‐1,2,4‐triazol‐1‐yl‐κN⁴)pent‐1‐en‐3‐ol]cobalt(II), [CoCl₂(C₁₅H₁₈ClN₃O)₄], was synthesized and structurally characterized by element analysis, IR spectrometry and X‐ray single‐crystal diffraction. The crystal structural analysis shows that the Co^II atom is located on the inversion centre and is coordinated by four uniconazole and two chloride ligands, forming a distorted octahedral geometry. The hydroxy groups of an uniconazole ligands of adjacent molecules form hydrogen bonds with the axial chloride ligands, resulting in one‐dimensional chains parallel to the a axis. The complex was analysed for its antifungal activity by the mycelial growth rate method. It was revealed that the antifungal effect of the title complex is more pronounced than the effect of fungicide uniconazole for Botryosphaeria ribis, Wheat gibberellic and Grape anthracnose.     

Cobalt‐based metal coordination polymers with 4,4′‐bipyridinyl groups: highly efficient catalysis for one‐pot synthesis of 3,4‐dihydropyrimidin‐2(1H)‐ones under solvent‐free conditions

Three new metal coordination complexes, namely [Co(BPY)₂(H₂O)₂](BPY)(BS)₂(H₂O)₄ ( 1 ), [Co(BPY)₂(H₂O)₄](ABS)₂(H₂O)₂ ( 2 ) and [Co(BPY)(H₂O)₄](MBS)₂ ( 3 ) (BPY = 4,4′‐bipyridine, BS = phenylsulfonic acid, ABS = p‐aminobenzenesulfonic acid, MBS = p‐methylbenzenesulfonic acid), were obtained under hydrothermal conditions. Complexes 1 , 2 , 3 were structurally characterized using single‐crystal X‐ray diffraction and infrared spectroscopy. All of them display low‐dimensional motifs: complex 1 displays a two‐dimensional structure; and complexes 2 and 3 exhibit a one‐dimensional tape structure. Through strong intermolecular hydrogen bonding interactions and weak packing interactions, all of them further stack to generate a three‐dimensional supramolecular architecture. Catalysts 1 , 2 , 3 were involved in the green synthesis of a variety of 3,4‐dihydropyrimidin‐2(1H)‐ones under solvent‐free conditions through Biginelli reactions. The corresponding catalytic product was obtained in quantitative yields (99%) under eco‐friendly synthesis conditions for the variety of reactions. Catalysts 1 , 2 , 3 exhibit excellent efficiency for the desired product, and their catalytic performance shows the following order: 2  >  1  ≈  3 , which can be ascribed to the hydrophobic interactions of different phenylsulfonate groups. The catalytic performance for the Biginelli reaction is not only dependent on the selected solvents, but also inversely proportional to the polarities of the solvents. Copyright © 2016 John Wiley & Sons, Ltd.     

Synthesis and Characterization of Novel Liquid Crystalline Epoxides with Lateral Substituent Showing Imposing Shape Memory Properties

In this work, a series of novel shape memory liquid crystalline (LC) epoxides with lateral substituent were prepared and characterized. Dynamic mechanical analysis (DMA) and shape memory testing were used to investigate on the thermo-mechanical properties and shape memory effects of prepared samples. The results showed that the modulus in the rubbery region (E_R ) decreased as the length of lateral alkyl group increases. And more than 95% of the deformation can be fixed as the sample was cooled down below the glass transition temperature (T_g), which was determined by differential scanning calorimetry (DSC) measurement, and can be recovered completely as heating. Effects of the curing agent and substituent on the shape memory behavior were also studied. We found that LC epoxides cured by aromatic diamine have a higher recovery speed. The recovering speeds of the shape memory decreased as the length of lateral alkyl group inscreased. The local ordered structures and the lateral substituent played an important role in shape memory effects.     

A Convenient Synthesis of α,β-unsaturated Nitriles

α,β-unsaturated nitriles were synthesized by the reaction of aldehydes with bromoacetonitrile promoted by tri-n-butylphosphine and zinc.     

A compact diode-pumped Q-switched and mode-locked Nd:GdVO4 laser based on SESAM

We report a compact passively Q-switched and Mode-locked Nd:GdVO₄ laser based on a semiconductor saturable absorber mirrors (SESAM). At a pump power of 12 W, the average output power was obtained to be 1.8 W with the repetition rate of the Q-witched envelope 80 kHz and 500 ns pulse width. The mode-locked pulses interval within the Q-switched envelope was about 1ns, corresponding to the high repetition of 1 GHz.     

On the Moment Convergence for Weighted Sums of Pairwise NQD Random Variables

Under the condition of h-integrability with respect to an array of weights, the moment convergence for weighted sums of pairwise negative quadrant dependent random variables is studied. The authors obtain a new result, and solve the open problem in Sung et al. ,(2008) and improve the corresponding theorem of Cabrera and Volodin (2005).     

Non-specular reflection of self-collimated beams in photonic-crystal-made prism and waveguide system

We demonstrate a dual-beam-reflection phenomenon for a Gaussian beam illuminating at a Kretschmann configuration composed of a photonic-crystal-made prism and a dielectric waveguide. One reflection beam has a positive shift and the other has a negative shift. The finite-difference time-domain (FDTD) shows that the specific phenomenon takes place only when the corresponding quasi-guided mode supported in the Kretschmann configuration is excited. Field profile of the quasi-guided mode demonstrates a strong localized stationary field in the dielectric waveguide. We found that the maximum positive lateral shift (LS) is 14.27a (where a is the lattice constant), corresponding to 3.07 times of the incident wavelength, which is 0.7135 times of the beam waist and much larger than that in some previous reports.     

Microwave-assisted one-pot three-component polymerization of alkynes,aldehydes and amines toward amino-functionalized optoelectronic polymers

We present a microwave-assisted one-pot polymerization with three-components of alkynes, aldehydes and amines for the synthesis of new amino-functionalized optoelectronic polymers. The polymerization of diynes(1a-1c), dialdehydes(2a and 2b) and dibenzylamine catalyzed by InCl_3 was carried out smoothly within 1h under microwave radiation, yielding four soluble polymers with high molecular weights. The resulting polymers P1 and P2 could be easily dissolved in alcohol and thus utilized as the cathode interlayer for polymer solar cells(PSCs). Compared with the control device, the PSCs with P1 and P2 as the cathode interlayer and PTB7-Th:PC_(71)BM as the photoactive layer exhibited significantly higher power conversion efficiencies(PCEs) of 9.49% and 9.16%, respectively. These results suggest that this polycoupling reaction is an efficient approach to construct three-component polymers for the practical applications.     

磁力平衡悬梁式液体界面张力仪的研制

液体界面张力系数是液体的重要物性参数之一,实现液体界面张力系数的精确测量具有重要的应用价值,所以我们以吊环法为基础开发出一套新型液体界面张力仪,该型仪器借助杠杆原理,利用霍尔式位移传感器以及永磁/电磁复合磁悬浮技术,通过对一个单摆式悬梁悬浮状态的监测和控制,将作用于金属吊环上的拉力适度放大并反映为电磁线圈的工作电流,进而实现液体界面张力的电法精确测量.所设计的仪器结构简单、测量精确、重复性好.