新型手性Salen双核锌配合物的分子识别研究

合成了新型手性Salen配体（H3L）及新型手性Salen双核锌配合物（主体）.通过研究主体对咪唑类客体及氨基酸酯类客体的分子识别行为,测定了这些配位反应的缔合常数.主体对咪唑类客体分子识别的缔合常数顺序为:K(Im) >K(2-MeIm) >K(2-Et-4-MeIm).主体对氨基酸酯类客体分子识别的缔合常数顺序为:K(LeuOCH3) >K(ValOCH3) >K(AlaOCH3) >K(SerOCH3),配位数均为2.主体与D、 L型氨基酸酯分子识别反应在不同温度下的缔合常数结果表明,随着温度的升高,对映选择性下降.实验发现反应体系中存在焓熵补偿关系. CD光谱的研究结果也反映了主体对不同客体识别能力的差异.     

相转移催化合成增塑剂BBP和水杨醛的研究

相转移催化合成增塑剂ＢＢＰ和水杨醛的研究郭锡坤，高文华，曾东宇（汕头大学化学系，汕头５１５０６３）关键词相转移催化，季铵盐，聚乙二醇，邻苯二甲酸丁苄酯，水杨醛，增塑剂邻苯二甲酸丁苄酯（增塑剂ＢＢＰ）是一种优良的增塑剂．邻羟基苯甲醛（水杨醛）不仅是重要...     

Determination of trace rhodium by supramolecular catalytic kinetic spectrofluorimetry of β-CD-rhodium-KBrO3-vanillin salicylhydrazone

A sensitive catalytic kinetic spectrofluorimetric approach for determining ng mL⁻¹ levels of rhodium is presented, and the possible mechanism of the catalytic reaction was investigated. The determination is based on the catalytic property of rhodium to enhance the reaction of o-vanillin salicylhydrazone (OVSH) with potassium bromate in a water-ethanol medium at pH 4.80 and 45 °C. The presence of β-cyclodextrin (β-CD) obviously sensitized the assay due to its high inclusion ability towards OVSH. Under optimized experimental conditions, fluorescence measurements of the β-CD-rhodium-KBrO₃-OVSH catalytic kinetic reaction system were carried out in its fluorescent band centered at λ_ex = 333 nm and λ_em = 476 nm, respectively. The calibration graph was linear over the concentration range of 0.47–100 ng mL⁻¹ with a detection limit of 0.14 ng mL⁻¹. The effect of interferences was discussed, and the results show that the extraction method can be used to separate rhodium from interference species such as iridium. The proposed method, applied to several synthetic mixtures containing rhodium mixed with varying amounts of metal salts, produced satisfactory results.     

Crystal Structure and Characterization of 2-N-(2-Hydroxy-benzylidene) Furanmethanoamine Nickel(II) Complex

1 INTRODUCTION Recently, the low-spin square-planar nickel(II) complexes and high-spin octahedral nickel(II) complexes with Schiff base ligands have received much attention in optical materials[1～3]. Some nic- kel(II) complexes are widely used as lubricating oil, rubber industry additives, a fire-resistant additive and fungicide for leather[4～7]. Also, their adducts with nitrogen have attracted broad attention due to their potential applications as organic conductors and magnetic mate…     

Differential pulse polarographic determination of salicylaldehyde as its Girard-P derivative

A method for the determination of salicylaldehyde (2 × 10^–6–10^–4 M) by differential-pulse polarography, based on the in situ formation of its Girard-P derivative in aqueous solution at pH 2.5, is proposed. The relative standard deviation was 1.5% (ten determinations of 4 × 10^–5 M level). The applicability of this method was checked in synthetic samples containing salicyl alcohol,o-aminophenol, 2-methylphenol, salicylic acid and 4-aminobenzoic acid.     

对氟苯甲醛水杨酰腙镍(II)配合物的合成、表征及其晶体结构

A nickel(II) complex Ni(C₁₄H₁₀N₂O₂F)₂ was synthesized from p-fluorobenzaldehyde salicylhydrazone and Ni(CH₃COO)₂·4H₂O and crystallized by diffusion, the structure of which was characterized by IR spectrum, ¹H NMR, and X-ray single-crystal diffraction. The complex crystallizes in monoclinic space group C2/c with a=2.460 6(2) nm, b=0.774 1(1) nm, c=1.534 9(1) nm, β=122.300(1)°, and V=2.471 1(4), Z=8, D_c=1.541 g·cm^-3. We reported the IR, ¹H NMR, crystal structure. CCDC: 638652.     

Reactions of salicylaldehyde with tris(pentaf luorophenyl)silanes and secondary amines

Reactions of tris(pentafluorophenyl)silanes RSi(C₆F₅)₃ with salicylaldehyde and secondary amines were studied. The reactions afforded α-pentafluorophenyl-substituted amines. Silanes RSi(C₆F₅)₃ (R = Me, Ph, C₆F₅, CH₂CH=CH₂, and CH=CH₂) were found to be efficient reagents for transfer of the C₆F₅ group to the iminium cation generated from salicylaldehyde and amine. However, tris(pentafluorophenyl)phenylethynyl-and tris(pentafluorophenyl)silanes were not able to serve as a source of a fluorinated substituent because of competitive transfer of acetylenide fragment or hydride. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 498–503, March, 2006.     

Determination of hydrazine and 1,1-dimethylhydrazine as salicyldehyde derivates by liquid chromatography with electrochemical detection

Summary Determination of hydrazine and 1,1-dimethylhydrazine after derivatization with salicylaldehyde was done using high-performance liquid chromatography with electrochemical detection. The oxidation of the phenolic group of salicylaldazine (S-HY) and salicylaldehyde-1,1-dimethylhydrazone (S-UDMH) was optimized with respect to ionic strength, pH, and applied potential. Less than 5 ng of S-HY and S-UDMH could be detected. The detection limits for hydrazine and 1,1-dimethylhydrazine solutions were estimated to be 0.025 and 0.20 ppm, respectively.     

异烟酰肼缩水杨醛Schiff碱及其铜(Ⅱ)配合物的合成及表征

制备了异烟酰肼缩水杨醛Schiff碱(H2L)及其铜(II)配合物,经元素分析、IR光谱、UV-Vis光谱、电导率和热分析表征,确定了配合物的组成为[Cu(NO3)HL].2H2O,其中H2L=C13H11O2N3.     

Synthesis and study of binuclear vanadyl complexes with acyldihydrazones of salicylaldehyde and dicarboxylic acids

The binuclear vanadyl(ii) complexes [(VO)₂·2Py·2EtOH]·mH₂O with acyldihydrazones of salicylaldehyde (H₄L) and dicarboxylic acids were synthesized and studied. In these complexes, two chelate vanadyl(ii) complexes with the tridentate bicyclic ligands are linked to each other by the polymethylene bridges —(CH₂) _n — of different lengths varying from one to four units. The ESR spectra of solutions of these complexes, unlike those of analogous copper(ii) complexes, have an isotropic signal with an eight-line hyperfine structure (g = 1.972, a _V = 93·10^–4 cm^–1) typical of monomeric vanadyl complexes, which indicates that no exchange interactions occur between the paramagnetic centers through the polymethylene chain.