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1.
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. 相似文献
2.
3.
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… 相似文献
4.
Luís J. Moreno López Manuel Callejón Mochón Juán C. Jiménez Sánchez Alfonso Guiraúm Pérez 《Mikrochimica acta》1996,124(3-4):187-194
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. 相似文献
5.
A. D. Dilman D. E. Arkhipov P. A. Belyakov M. I. Struchkova V. A. Tartakovsky 《Russian Chemical Bulletin》2006,55(3):517-522
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. 相似文献
6.
Determination of hydrazine and 1,1-dimethylhydrazine as salicyldehyde derivates by liquid chromatography with electrochemical detection 总被引:1,自引:0,他引:1
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. 相似文献
7.
8.
Shul"gin V. F. Zlatogorskii S. M. Zub V. Ya. Larin G. M. 《Russian Chemical Bulletin》2002,51(12):2273-2276
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. 相似文献
9.
《Arabian Journal of Chemistry》2020,13(1):1198-1228
Vanadate and vanadium compounds exist in many environmental, biological and clinical matrices, and despite the need only limited progress has been made on the analysis of vanadium compounds. The vanadium coordination chemistry of different oxidation states is known, and the result of the characterization and speciation analysis depends on the subsequent chemistry and the methods of analysis. Many studies have used a range of methods for the characterization and determination of metal ions in a variety of materials. One successful technique is high performance liquid chromatography (HPLC) that has been used mainly for measuring total vanadium level and metal speciation. Some cases have been reported where complexes of different oxidation states of vanadium have been separated by HPLC. Specifically reversed phase (RP) HPLC has frequently been used for the measurement of vanadium. Other HPLC methods such as normal phase, anion-exchange, cation-exchange, size exclusion and other RP-HPLC modes such as, ion-pair and micellar have been used to separate selected vanadium compounds. We will present a review that summarizes and critically analyzes the reported methods for analysis of vanadium salts and vanadium compounds in different sample matrices. We will compare various HPLC methods and modes including sample preparation, chelating reagents, mobile phase and detection methods. The comparison will allow us to identify the best analytical HPLC method and mode for measuring vanadium levels and what information such methods provide with regard to speciation and quantitation of the vanadium compounds. 相似文献
10.
Cerium(III) chloride heptahydrate (CeCl3·7H2O) catalyzes the reaction of substituted salicylaldehydes with 1,3-cyclohexane dione or dimedone in aqueous medium at reflux temperature to afford the corresponding 1-oxo-1,2,3,4,9,10-hexahydroxanthene derivatives4 0 in high yields. 相似文献