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A simple and efficient access to arylboronates was achieved with methanol-initiated borylation of aryldiazonium salts. Reduction of aryldiazonium ions by single electron transfer from methanol affords aryl radical species, which undergo a subsequent C–B bond formation with bis(pinacolato)diboron. This highly practical borylation process, which can be carried out on the gram-scale, enjoys operational simplicity as well as mild and catalyst-free conditions.

Two new bis-Schiff bases containing a piperazine ring, N,N‘-bis(4-chlorobenzylidene)- and N,N‘-bis(4-cyanobenzylidene)-1,4-bis(3-aminopropyl)piperazine, were prepared by the reaction of N,N‘-bis(3-aminopropyl)piperazine with 4-chloro- and 4-cyanobenzaldehyde, respectively. The dichloro compound was fully identified by X-ray crystallography and it exhibited good antibacterial activity against Escherichia coli, Staphylococcus aureus and Bacillus subtilis.

Two new Schiff base zinc(II) complexes, [ZnBr2L] (I) and [ZnCl2L] (II), where L is 4-bromo-2-[(3-diethylaminopropylimino)methyl]phenol, were synthesized and characterized by physico-chemical methods and single crystal X-ray diffraction. The crystal of I is monoclinic: space group P21/n a = 7.250 (2), b = 16.136 (3), c = 15.802 (3) A, β = 90.027 (3)°, V = 1848.6 (7) A3, Z = 4. The crystal of II is monoclinic: space group P21/n, a = 7.177 (3), b = 15.970 (4), c = 15.689 (3), β = 91.674 (3)°, V = 1797.5 (9) A3, Z = 4. The Zn atom in each complex is four-coordinated by one phenolate O and one imine N atoms of the Schiff base ligand and two halide atoms, forming a tetrahedral coordination. The urease inhibitory activities of the complexes were evaluated.

Two mononuclear nickel(II) complexes, [Ni(MMP)(NCS)] (1) and [Ni(PMP)(NCS)] (2), where MMP = 5-methoxy-2-[(2-morpholin-4-ylethylimino)methyl]phenolate, PMP = 5-methoxy-2-[(pyridin-2-ylmethylimino)methyl]phenolate, were prepared and structurally characterized by X-ray diffraction. The Ni atom in each complex is four-coordinated by three donor atoms of the Schiff base ligand, and by one thiocyanate N atom, forming a square planar coordination. The urease inhibitory activity of the complexes was evaluated.

A novel coordination polymer, [Cd2(PMP)2Cl4] n (PMP = 1-phenyl-3-methyl-2-pyrazoline-5-one), was prepared by the reaction of cadmium chloride hemidihydrate and PMP, and characterized by elemental analysis, IR spectrum, TGA/DTA and electrochemical analysis. Single crystal X-ray diffraction revealed that the title complex is orthorhombic, space group Pna2(1), with a = 16.5398(14), b = 18.238(2), c = 3.8367(7) A, V = 1157.4(3) A3, Z = 2. Each cadmium atom is hexa-coordinate and surrounded by an OCl5 environment, adopting a distorted octahedral geometry, in which three Cl− ions act as μ3-linker and two as μ2-linker. The Cd(II), Cl− and PMP form an infinite 1D chain with complicated chair-like features through μ2- and μ3-Cl bridges. The electrochemical behavior of the complex was investigated in DMF by cyclic voltammetry. The antibacterial activity of the complex, PMP and cadmium chloride hemidihydrate was tested against Escherichia coli, Staphylococcus aureus and Bacillus subtilis by the agar diffusion method.

A centrosymmetric phenolate oxygen bridged dinuclear copper(II) complex [Cu2(L1)2(N3)2] (1) and a mononuclear zinc(II) complex [Zn(L2)(NCS)2] (2), where HL1 = 2-[1-(pyridin-2-ylmethylimino)ethyl]phenol and L2 = (1-pyridin-2-ylethylidene)pyridin-2-ylmethylamine, were synthesized and structurally characterized by physicochemical methods and single-crystal X-ray diffraction. The Cu atom in (1) is five-coordinated in a slightly distorted square pyramidal geometry, and the Zn atom in (2) is five-coordinated in a severely distorted square pyramidal geometry.

A new Schiff base, N,N′-bis(4-methoxy-benzylidene)-1,4-bis(3-aminopropyl)piperazine (BMBA), has been synthesized by the reaction of 1,4-bis(3-aminopropyl)piperazine and 4-methoxy-benzaldehyde in methanol solution. The title compound was characterized by elemental analysis, IR spectrum, 1H NMR, 13C NMR and X-ray single crystal diffraction analyses. The compound crystallizes in the monoclinic system with space group C2/c and a = 24.071(5), b = 9.4035(19), c = 11.263(2) A, β = 96.787(2)°, V = 2531.6(9) A3, D c = 1.193 g/cm3, M r = 454.60, Z = 4, F (000) = 984, μ = 0.079 mm−1, R 1 = 0.0693, and ωR 2 = 0.2269. In the crystal structure, molecules of BMBA and water of crystallization are linked through intermolecular O2W–H2′···N2 hydrogen bond, forming a 1D hydrogen bonding network that generates planar “ribbons” running parallel to the c-axis. Furthermore, the antibacterial activity of title compound was investigated preliminary by agar diffusion method, and it exhibited certain inhibited effect against Escherichia coli, Staphylococcus aureus and Bacillus subtilis. A new Schiff base, N,N′-bis(4-methoxy-benzylidene)-1,4-bis(3-aminopropyl)piperazine, has been synthesized by the reaction of 1,4-bis(3-aminopropyl)piperazine and 4-methoxy-benzaldehyde in methanol solution, and characterized by elemental analysis, IR spectrum, 1H NMR, 13C NMR and X-ray single crystal diffraction analyses. Furthermore, the antibacterial activity was investigated by agar diffusion method, and the results indicated that the Schiff base was active relatively against Escherichia coli, Staphylococcus aureus and Bacillus subtilis.

A new polynitrile, N,N,N′,N′-tetra(2-cyanoethyl)-1,4-bis(3-aminopropyl)piperazine, was synthesized by the nucleophilic addition reaction of 1,4-bis(3-aminopropyl)piperazine and acrylonitrile for the first time. The title compound was characterized by elemental analysis, IR spectrum, and its crystal structure determined by X-ray single-crystal diffraction. The compound crystallizes in the monoclinic system with space group P2 1/c and a = 8.6195(12), b = 9.300(14), c = 16.221(2) A, β = 97.824(2)°, V = 1288.2(3) A3, D c = 1.064 g cm−3, M r = 412.59, Z = 2, F(000) = 448, μ = 0.067 mm−1. The TG–DTA analysis revealed that the title compound possesses relatively good thermal stability under 220 °C. A new polynitrile, N,N,N′,N′-tetra(2-cyanoethyl)-1,4-bis(3-aminopropyl)piperazine, was synthesized and characterized by elemental analysis, IR spectrum, TG–DTA, and X-ray single-crystal diffraction.

A new Cd(II) coordination polymer, [Cd(PMP)2] n (1) [PMP = 1-phenyl-3-methyl-5-pyrazolone], has been synthesized by the reaction of Cd(CH3COO)2·2H2O with PMP and characterized by elemental analysis, IR spectrum, fluorescence spectrum, UV–vis spectrum, TG–DTA, and electrochemical analysis. Single crystal X-ray diffraction reveals that the complex has a three-dimensional network. Each PMP acts as bidentate bridging ligand and each Cd(II) center is surrounded by two O atoms and two N atoms from four different PMP ligands to form distorted tetrahedral coordination geometry. The photoluminescence study shows the complex exhibited strong solid state blue fluorescent emission at room temperature, and the TG–DTA analysis demonstrated that it has highly thermal stability. Furthermore, the electrochemical property of the complex has been investigated for the first time in DMF by cyclic voltammetry, and the results showed that it has an irreversible process.

A new coordination polymer [Zn(PMP)2Cl] n (PMP = 1-phenyl-3-methyl-5-pyrazolone) has been prepared by the reaction of zinc chloride and PMP, and characterized by elemental analysis, IR, UV, and fluorescence spectra, TG/DTA, and electrochemical analysis. Single crystal X-ray diffraction revealed that the complex is monoclinic, space group P 2(1)/n, with a = 10.850(17), b = 17.578(2), c = 10.997(18) A, β = 104.999(3)°, V = 2025.8(5) A3, Z = 4, Dc = 1.470 mg m−3, F(000) = 920, goodness-of-fit = 0.905, and R 1 = 0.0441. The complex is a 1-D coordination polymer, and the coordination geometry of Zn(II) is a distorted tetrahedron.

A new copper Schiff-base complex [Cu(C15H23N3O2)(NO3)]NO3 was synthesized and characterized by spectroscopic (IR), thermal (TG/DTA) and electrochemical methods. Single crystal X-ray diffraction revealed that the complex is monoclinic, space group P2(1)/c, with a = 23.549(2), b = 6.583(12), c = 12.765(15) A, β = 102.823(2)°, V = 1929.4(5) A3, Z = 4, D calcd = 1.601 Mg m−3, F(000) = 964, goodness-of-fit = 1.034 and R 1 = 0.0407. The Cu(II) is four-coordinate with distorted square planar geometry. The structure consists of isolated [Cu(C15H23N3O2)(NO3)]+ and a nitrate, which are further linked to a 3D network by significant N–H ··· O, N–H ··· N hydrogen bonds and weak O ··· Cu interaction.

The Willgerodt-Kindler reaction of acetophenone was studied. Apart from the normal product 4-(benzylthiocarbonyl)morpholine, another product 4-(benzoylthiocarbonyl)morpholine was obtained unexpectedly. The structure of the latter was confirmed by IR, 1H NMR spectra and X-ray diffraction analysis. The mechanism of the reaction was discussed.

The mol­ecule of the title compound, C28H42N6, has site symmetry \overline{1} with the centroid of the piperazine ring located on an inversion center. The piperazine ring adopts a chair conformation. The benzene ring and propyl­piperazine are on opposite sides of the C=N bond, showing an E configuration.

The title compound, C2H10N2 2+·2C10H9N2O−, is composed of deprotonated 5-methyl-2-phenyl-1H-pyrazol-3(2H)-one anions (PMP−) and protonated ethylenediamine cations (H2en2+). The ethylenediammonium ion is located on a crystallographic inversion center. The dihedral angle between the phenyl and pyrazole rings is 39.73 (8)°. The two components are connected through N—H...O and N—H...N hydrogen bonds, forming an infinite three-dimensional network.

In order to gain the optimal extract condition of extraction polysaccharides in Loquate leaf by ultrasound technique, the single factor and the orthogonal experiments were carried. The results showed that the optimal condition turned out to be ultrasound extraction time 35 min, ultrasound power 120W, extraction temperature 60 degrees C and the liquid-to-solid ratio 12: 1. In contrast to conventional extraction method, the ultrasound technique could be a better method for extracting the polysaccharides from Loquat leaf with a higher yield and shorter time.

In order to obtain the theoretical mass transfer model in the process of extracting effective ingredients from natural plant by Supercritical Fluid, the mass transfer mechanism was analyzed and the analytical solution of the dynamic model of Supercritical Fluid Extraction was deduced through rational simplifying the differential mass balance equations. The complete extraction time, extraction yield as a function of time and the influence of the diameter of solid material on the extraction yield were calculated by the model and the results of computation fit well with the experimental data of literature. This model can be used to analyze, predict, design and optimize the process of extracting effective ingredients from natural plant by Supercritical Fluid.