羟氨(H2NOH)重排反应的理论研究

羟氨H_2NOH是人们所熟知的分子,但至今还没有确切的实验证据证实有氨氧化物H_2NO的存在,尽管其取代物R_3NO已被分离出。鉴于类羟氨R_2NOH和N-氧化物在生物学上的重要意义,研究H_2NOH和H_3NO的结构以及二者重排反应的动力学行为就成了一个重要课题。本文用内禀反应坐标方法对此反应进行了反应路径解析,并给出了沿反应途径上的振动频率相关。     

A Cyclic Hydroxylaminato‐aminoxide Complex of Gallium

The reaction of HON(tBu)CH₂CH₂N(tBu)OH with tri‐tert‐butyl gallium affords a hydroxylaminato complex of the formula [tBu₂Ga{ON(tBu)CH₂CH₂N(H)(tBu)O}], which contains a monoanionic bishydroxylaminato ligand with one anionic and one neutral, but tautomeric aminoxide end, both linked to gallium by their oxygen atoms leading to a seven‐membered ring. The compound was characterised by elemental analysis, ¹H and ¹³C NMR and determination of its crystal structure.     

Electrocatalytic Characteristics of Hydrazine and Hydroxylamine Oxidation at Coumestan Modified Carbon Paste Electrode

A coumestan derivative modified carbon paste electrode (CMCPE) was used as a sensitive electrochemical sensor for determination of electrocatalytic of hydrazine and hydroxylamine. The mechanism of electrocatalytic oxidation of both hydrazine and hydroxylamine using CMCPE was investigated by cyclic voltammetry and polarization studies. The kinetic parameters such as the electron transfer coefficient, α, heterogeneous rate constant, k′, and exchange current density, j₀, for oxidation of hydrazine and hydroxylamine at the CMCPE surface were determined using cyclic voltammetry. Further more, the linear dynamic range, sensitivity and limit of detection for hydrazine and hydroxylamine detections were evaluated using differential pulse voltammetry.     

Combination of NH2OH·HCl and NaIO4: a new and mild oxidizing agent for selective oxidation of alcohols to carbonyl compounds

A new method for oxidation of alcohols to carbonyl compounds has been developed using NH₂OH·HCl and NaIO₄ under mild reaction conditions at room temperature. Application of the method for the synthesis of diiodo compound from α,β-unsaturated carbonyl compound is also described.     

Direct Synthesis of Nitriles from Aldehydes in Ionic Liquids

1 Introduction Ionic liquids(ILs) are environmentally acceptable solvents because they have low vapor pressure,high thermal stability and chemical stability,excellent solvent for organic and inorganic compounds. Therefore,they can be used as green solvents for a number of chemical processes,such as separations and reactions [1,2].     

利用偶联反应光度法测定羟胺体系的研究及应用

利用羟胺与碘反应生成亚硝酸 ,然后与对氨基苯磺酸发生重氮化反应 ,再与 α-萘胺偶联形成偶氮化合物 ,从而建立了测定羟胺的新光度法。方法线性范围为 2 .0× 1 0 - 6 ～1 .5× 1 0 - 5mol/L ,表观摩尔吸光系数为 3.1× 1 0 4 L· mol- 1· cm- 1,应用于水中羟胺和试剂丁二酮肟含量的测定 ,结果满意。     

铜磷钼酸分光光度法间接测定盐酸羟胺

在pH3．0的Clauk-Lubs缓冲溶液中,基于盐酸羟胺能定量地将铜磷钼杂多酸还原为铜磷钼蓝的现象,建立了分光光度法间接测定盐酸羟胺的方法。结果表明,测定的线性范围是0～7．68μg／mL,相关系数r=0．9996,RSD为0．43％(n=6)。方法简便快捷,准确可靠。用于工业盐酸羟胺的测定,结果满意。     

Novel synthetic route of aryl-aminopyrazine

We report a novel synthetic route of aryl-aminopyrazine through a new cyclization reaction by using a hydroxylamine. Starting from Boc-glycine and aminonitrile, the aminopyrazine ring was prepared in several steps. After trifluoromethane sulfonylation of the aminopyrazinone, the resultant triflate was subjected to Suzuki-Miyaura coupling reaction with aryl boronic acid to afford coelenteramine.     

Fe(Ⅲ)-5-Br-PADAP-CTMAB体系间接分光光度法测定盐酸羟胺

在 CTMAB存在下 ,基于盐酸羟胺能定量还原 Fe( )离子为 Fe( )离子 ,利用显色剂 5 - Br- PADAP建立了间接分光光度法测定盐酸羟胺的方法。在 p H3.6的 KHC8H4 O4 - HCl缓冲溶液中 ,Fe( ) - 5 - Br-PADAP络合物的最大吸收峰位于 75 0 nm处。盐酸羟胺含量在 0— 35 μg/ 2 5 m L范围内符合比耳定律 ,ε=2 .4 0× 10 4 L·mol-1·cm-1。本方法用于盐酸羟胺 (工业品 )的测定 ,结果令人满意。