吡唑铜(Ⅱ)配合物的合成、晶体结构及性质

本文报道了Cu(Ⅱ)的吡唑和硫氰酸根混合配体配合物[Cu(pz)₄(NCS)₂](1)(pz=吡唑)的合成、晶体结构及性质.配合物属单斜晶系,C2/c空间群,a=1.1520(4) nm,b=1.2247(4) nm,c=1.4188(5), β=106.747(8)°, Z=4, R₁=0.0554, wR₂=0.1420.配合物中Cu(Ⅱ)与4个吡唑环上的4个N原子及2个NCS^-的N原子配位形成4+2型拉长八面体配位环境,4个吡唑环上的N原子占据赤道位置, 2个NCS^-的N原子占据轴向位置.对配合物的IR、UV-Vis、ESR进行表征和分析.比较不同轴向配体对结构和性质的影响.     

以脲和硫氰酸盐为主体的高分子固体电解质的研究

在熔盐体系相图指导下研制出以脲和硫氰酸铵(钾)为主体的高分子固体电解质(PSE),其室温电导率分别为1.20×10^-2和2.65×10^-3S/cm.考察了影响该PSE电导率的因素,讨论了PSE的导电机理.结果表明,所研制的PSE为无定形固熔体,主要通过硫氰酸盐的电离导电,电导率-温度关系服从VTF方程.     

Determination of thiocyanate as a biomarker of tobacco smoke constituents in selected biological materials of human origin

In order to protect human health, it is necessary to biomonitor toxic substances originating from tobacco smoke in biological materials sampled from persons with different exposures to tobacco smoke constituents. Thiocyanate anion is a biomarker of exposure to tobacco smoke components which is characterized by a relatively long half‐life in the human body, i.e. 6 days. In this work, we present the results of thiocyanate determinations performed on samples of placenta, meconium, saliva, breast milk, sweat and blood. The placenta samples were subjected to accelerated solvent extraction with water. The thiocyanate concentrations were determined using ion chromatography. The analyzed biological materials were compared with regard to their applicability for biomonitoring toxic substances originating from tobacco smoke. The highest mean concentrations of thiocyanate were observed in the samples of biological materials collected from active smokers.     

Rapid and simple detection of sodium thiocyanate in milk using surface‐enhanced Raman spectroscopy based on silver aggregates

Surface‐enhanced Raman spectroscopy (SERS) was used for rapid detection of sodium thiocyanate in milk employing silver aggregates as active substrate. Silver nanoparticles were induced to silver aggregates by trichloroacetic acid (TCA). The limit of detection (LOD) for sodium thiocyanate was 10⁻² µg ml⁻¹ in water with an analytical enhancement factor of 5.4 × 10⁶. The silver aggregates represent good reproducibility and stability. Good linear relationship was obtained for sodium thiocyanate in milk at concentration ranges from 0.1 to 10 µg ml⁻¹ (R² = 0.995). Using TCA as protein precipitator, silver colloid would aggregate spontaneously when mixing with samples during SERS measurement without the need of additional aggregating agent. The simple pretreatment procedures and analytical methods are less time consuming (<10 min) and environmentally friendly, making the proposed method much practical for in situ detection of sodium thiocyanate in market milk. Copyright © 2014 John Wiley & Sons, Ltd.     

4-Aminophenyl Diphenylphosphinite (APDPP) as a Heterogeneous and Acid Scavenger Reagent for Thiocyantion or Isothiocyanation of Alcohols and Protected Alcohols

4-Aminophenyl diphenylphosphinite (APDPP) as a heterogeneous phosphinite reagent is used for the efficient conversion of alcohols, trimethylsilyl- and tetrahydropyranyl ethers, α -hydroxy phosphonates, and α -trimethylsilyloxyphosphonates to their corresponding thiocyanates or isothiocyanates in the presence of Br ₂ and NH ₄ SCN.     

Chlorodiphenylphosphine as Highly Selective and Efficient Reagent for the Conversion of Alcohols,Tetrahydropyranyl and Silyl Ethers to Thiocyanates and Isothiocyanates

Abstract

A simple, highly selective and efficient method is described for the conversion of primary alcohols, tetrahydropyranyl and silyl ethers to thiocyanates by use of chlorodiphenylphosphine and ammonium thiocyanate. Secondary substrates produce both the two isomeric products, thiocyanate and isothiocyanate, while tertiary ones give isothiocyanates as the only products by this new method. In contrast to previously reported methods based on trivalent phosphorus for this transformation, the present method does not require an electrophile in the presence of trivalent phosphorus (ClPPh₂). The order of activity of these substrates is silyl ether> alcohol > tetrahydropyranyl ether. The present method not only interestingly distinguishes between primary, secondary and tertiary substrates but also converts them to the corresponding thiocyanates with excellent chemoselectivity in the presence of several other functional groups.     

Generation of the [NiFe] Hydrogenase Active Site (Sulfur's the One!)

Abstract

Chemical and biochemical methods were used to unravel the unprecedented pathway by which the CN ligands of iron in [NiFe] hydrogenase are introduced. Carbamoyl phosphate is the one carbon precursor of these ligands, and reactions involving a protein cysteinyl sulfur are key for processing this precursor into CN ligands.