Fabrication of ultra‐small ruthenium nanoparticles on porous modified reduced graphene oxide and its application in solvent‐free oxidation of cyclohexene with molecular oxygen

In the present work, ruthenium nanoparticles were synthesized on functionalized reduced graphene oxide (rGO). First, the surface of rGO was modified with two para‐arsanilic acid and dithiooxamide promoters to create the rGO with scattered hydrophilic positions. The ruthenium nanoparticles were synthesized and immobilized simultaneously in small hydrophilic micro‐reactors under mild conditions. Characterization of the synthesized nanocatalyst was confirmed with different techniques, such as transmission electron microscopy (TEM), X‐ray diffraction, Fourier transform‐infrared and scanning electron microscopy. TEM images of the synthesized catalyst show the Ru nanoparticles have diameters less than 6 nm. The designed nanocatalyst was investigated for the selective liquid phase oxidation of cyclohexene with molecular oxygen in an autoclave under solvent‐free conditions, which obtained a maximum of 91% conversion and 90% selectivity under optimized conditions. The catalytic activity over rGO‐AO‐TO/Ru recycled catalyst remained at a satisfactory state after at least five runs.     

A Spectrophotometric Study of the Determination of Copper with Dithiooxamide in Acidic Media

Abstract

A spectrophotometric method for the determination of copper has been developed based on the development of a red color in acidic solution using dithiooxamide as the chromogenic agent. The molar absorptivity is 7.04 × 10³ 1. mol^?1 cm^?1 at 525 nm. Relatively few ions interfere.     

Benzo-15-crown-5 1∶1 and 1∶2 complexes with dithiooxamide and thioacetamide

Benzo-15-crown-5 and thiooxamide in the 11 complex form infinite chains of alternating host-guest molecules. The host oxygen atoms are involved in six close interactions with amide hydrogen atoms forming one bifurcated and one single hydrogen interaction on each face. In the 12 complex the host forms a distinct molecular entity with two thioacetamide molecules. Again one bifurcated and one normal hydrogen...oxygen interaction occurs on each face. The conformation of the benzo-15-crown-5 host is the same in both complexes and agrees with a conformation of the free host calculated by molecular mechanics. The conformation of crystalline benzo-15-crown-5 differs from that calculated. In either case, no major conformational reorganization is required to accommodate the intermolecular interactions. The oxygen atoms of the benzo-15-crown-5 form an approximate pentagon with the amide nitrogen atoms lying 2.18(1) Å from the mean plane. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82041 (43 pages).     

2-(取代氨基硫代甲酰基)-3,4,5,6-四氢嘧啶的合成

以N,N'-二取代二硫代草酰胺与1,3-丙二胺在DMSO中进行缩合反应, 合成了一系列2-取代氨基硫代甲酰 基-3,4,5,6-四氢嘧啶, 反应在2 h内完成, 产率56%～76%. 产物结构经元素分析, IR, ¹H NMR及MS确证.     

在与水混溶的有机溶剂体系中流动注射光度法测定钯

本文研究了在乙醇－水载流体系中钯的流动注射光度法。二硫代乙二酰胺为显色剂，在波长４２０ｎｍ处检测，测定钯的线性范围为２．０～１２．０μｇ／ｍＬ，进样频率达２４０次／ｈ。方法有较好的选择性，适合于各种催化剂、合金和王水不溶渣中微量和较高含量钯的分析。     

二硫代乙二酰胺合镍在硫化镉纳米晶表面的逐层配位组装

CdS nanocrystals, which were surface modified by poly (nickel dithioxamide) [Ni(DTO)]_n, were prepared and characterized. TEM image showed that the shape and the outward aspect of the modified CdS sample were essentially the same as those of the original material and no impurities were found. The characteristic IR peaks at 1 513cm^-1 and 870 cm^-1 confirmed the success in assembling [Ni(DTO)]_n on the surface of CdS. For XPS spectra, the characteristic bands of Ni2p3/2 and Ni2p1/2 appeared at 856 eV and 877 eV indicating the nickel in Ni(Ⅱ) oxidation state. The solid state electronic spectra showed the improvement in surface energy gap, which was changed from 2.38 eV to below 1.91 eV.