均三嗪衍生物比色识别Cu2+及荧光识别Zn2+

以对氨基苯腈、邻叔丁基苯酚和3,5-二叔丁基水杨醛为原料合成了两种含有均三嗪对称结构的离子探针1和2,通过核磁共振氢谱、核磁共振碳谱、红外、质谱对合成产物进行表征,确认其结构。利用紫外吸收光谱和荧光光谱两种手段分别考察了探针1和探针2在N,N-二甲基甲酰胺（DMF）溶液中对金属离子（Cr³⁺、Mn²⁺、Fe³⁺、Co²⁺、Ni²⁺、Cu²⁺、Zn²⁺、Cd²⁺、Hg²⁺）的识别性能,通过核磁共振氢谱对探针1与Zn²⁺的识别机理进行研究。结果表明,两种探针热稳定性强,探针1溶液中加入Zn²⁺会引起荧光强度的显著增强,抗干扰性强,是一种高选择性识别Zn²⁺的荧光增强型探针;探针2中加入Cu²⁺后溶液由无色变成黄色,紫外光谱长波长处出现新吸收峰,是一种可裸眼识别的、高效的紫外Cu²⁺探针。     

水杨醛亚胺钛络合物的负载及在催化乙烯聚合中的应用

以3,5-二枯基水杨醛与2,3,4,5,6-五氟苯胺为原料缩合反应合成了水杨醛亚胺配体(Ⅰ),利用四氯化钛和水杨醛亚胺配体(Ⅰ)反应制得了相应的水杨醛亚胺钛络合物(Ⅱ),用核磁共振氢谱(1H NMR)和核磁共振碳谱(13C NMR)表征了配体及络合物的结构.以甲基铝氧烷(MAO)为助催化剂,在60℃、1.0 MPa压力...     

Vanadium peroxocomplexes as oxidation catalysts of sulfur organic compounds by hydrogen peroxide in bi-phase systems

New vanadium oxodiperoxocomplexes Bu₄N⁺[VO(O2)₂ L₂]⁻ were synthesized, where L=pyridine (1), 2-methylpyridine (2), 4-methylpyridine (3), 2-oxymethylpyridine (4). All complexes were characterized by NMR (¹H, ⁵¹V) and IR spectroscopy. The oxidation of sulfur organic compounds and diesel fuel desulfurization catalyzed by vanadium peroxocomplexes in bi-phase system was investigated in various solvents. The complexes manifested high catalytic activity and selectivity in oxidation of sulfides.     

多乙烯多胺桥联受阻酚类抗氧剂的合成及其清除DPPH·性能

以二乙烯三胺和三乙烯四胺为桥联基,β-(3,5-二叔丁基-4-羟基苯基)丙酰氯为抗氧化功能基团,通过酰胺化缩合反应合成了两类具有不同对位桥联基团的受阻酚类抗氧剂。采用傅里叶红外光谱和核磁共振氢谱证实了合成的多乙烯多胺桥联受阻酚类抗氧剂的化学结构。DPPH法研究了多乙烯多胺桥联受阻酚类抗氧剂清除自由基的性能,并探索了酚羟基个数和对位桥联基结构对受阻酚类抗氧剂清除自由基性能的影响。结果表明,多乙烯多胺桥联受阻酚类抗氧剂具有良好的清除DPPH·能力,且随着抗氧剂分子中酚羟基个数的增加,清除DPPH·的活性增加,分子中含有4个酚羟基的三乙烯四胺受阻酚类抗氧剂的抗氧化效率（AE）达到2.65×10^-2 L/(mol·s)。对位桥联基结构对受阻酚类抗氧剂清除DPPH·能力有较大影响,季戊四醇为桥联基的受阻酚类抗氧剂1010清除DPPH·能力最强,其抗氧化效率（AE）为3.08×10^-2L/(mol·s);乙二胺为核的1.0代树枝状受阻酚类抗氧剂清除DPPH·能力最弱,其抗氧化效率（AE）为2.60×10^-2 L/(mol·s)。     

Development of structural characterization and physicochemical behaviour of triphenylamine blocks

A novel multitriphenylamine substituted derivatives, possessing the respective photochromic groups were synthesized by Stille cross-coupling methodology. The hyperbranched structures have been characterized by ¹H NMR, ¹³C NMR. Obtained structures show good stability in common organic solvents such as CHCl₃, toluene and CH₂Cl₂ and exhibit excellent thermal stability. Electrochemical results and theoretical calculation suggest that oxidation and reduction start from the side of amine and branching five member heterocycle ring moieties, respectively.     

Al, N, C and H NMR spectra and negative-ion electrospray mass spectra of the 2:1 aluminium(III) complexes of azo dyes derived from anthranilic acid

The ²⁷Al, ¹⁵N, ¹³C and ¹H NMR spectra in DMSO and mass spectra of 2:1 aluminium(III) complexes (1b–4b) derived from anthranilic acid azo coupling products with 4-tert.butylphenol (1a), 2-naphthol (2a) acetoacetanilide (3a) 3-methyl-1-phenylpyrazol-5-one (4a) were measured and analysed. It was found that the aluminium atom was six-coordinated, being bound to two oxygens and the nitrogen originating from anthranilic acid.     

Electrochemical and spectroscopic properties of 1:2 Ni complexes of 1,3-substitued (CH3, OCH3) phenyl-5-phenylformazans

In this study, new 1:2 nickel complexes of 1-[o-, m-, p-(methyl, metoxyphenyl)]-3-(p-metoxyphenyl)-5-phenylformazans were synthesized. Their structures were elucidated and spectral behaviors were investigated with the use of elemental analysis, GC–mass, ¹H NMR, ¹³C NMR, IR, and UV–vis spectra. The redox characteristics of these compounds have been investigated in nonaqueous dimethylsulfoxide at platinum and ultramicro platinum (10 μm) electrodes. Through controlled potential electrolysis, the oxidation products of each class of compounds can be separated and identified. The oxidation mechanism is suggested and it is proved. It was observed the oxidation mechanism take place in a single step two-electron or one-electron transfer to a disproportionation or dimerization reactions following the radical formation step. Eventually the relation between their absorption properties and electrochemical properties was examined.     

IA/TPEC阻垢剂的合成及其性能

以甲基烯基聚氧乙烯醚(TPEG)、衣康酸(IA)为原料,在氧化/还原引发剂体系作用下进行自由基共聚,合成IA/TPEC阻垢剂。通过红外光谱(FTIR)、核磁共振氢谱(¹H NMR)等方法对阻垢剂结构进行表征。考察了单体配比、引发剂的种类和聚合条件等对合成IA/TPEC阻垢剂性能的影响。实验结果表明:当m(IA):m(TPEC)为1:1,在110℃下聚合1.5 h,采用过硫酸铵/次亚磷酸钠为引发剂体系,合成的IA/TPEC对CaCO₃和Ca₃(PO₄)₂的阻垢率分别为90.19%和92.71%,阻垢效果优于市售阻垢剂。     

V2O5 catalysts supported on Al2O3–SiO2 mixed oxide: V, H MAS solid-state NMR, DRIFTS and methanol oxidation studies

Alumina–silica mixed oxide, synthesized by the sol–gel technique, was used as a support for dispersing and stabilizing the active vanadia phase. The catalysts were characterized employing ⁵¹V and ¹H solid-state MAS NMR, diffuse reflectance FT-IR, BET surface area measurements. The partial oxidation activities of the catalysts were tested using methanol oxidation as a model reaction. ⁵¹V solid-state NMR studies on the calcined catalysts showed the peaks corresponding to the presence of both tetrahedral and distorted octahedral vanadia species at low vanadia loadings and with an increase in V₂O₅ content, the ⁵¹V chemical shifts corresponding to amorphous V₂O₅ like phases were observed. DRIFTS studies of the catalysts indicated the vibrations corresponding tetrahedral vanadia species at low and medium loadings and at high V₂O₅ contents the vibrations corresponding V=O bonds of V₂O₅ agglomerates were observed. The V/Al–Si catalysts exhibited high selectivity for the dehydration product dimethyl ether in the methanol partial oxidation studies showing the predominance of the acidic nature of the alumina–silica support over the redox properties of the active vanadia phase.     

Conversion of propylene into cyclohexane on PtGaZr/SiO2 catalyst

The light olefins present in Delay Coker and fluid catalytic cracker dry gas can be valorized into naphthenes using a new PtGaZr/SiO₂ catalyst. This catalyst was compared to a GaZrSiO₂ catalyst prepared with the same methodology. Both were characterized by XRD, and FTIR, XPS, ⁷¹Ga, ²⁹Si and ¹H NMR spectroscopies. Propylene is treated in the presence of CS₂, hydrogen, and benzene in a semi-batch type reactor and the product composition is analyzed by GC and MS techniques. The different operating variables were explored to study the effect of Pt on activity, selectivity and catalyst stability. The spent catalysts after 10 cycles in operation were analyzed using ¹³C NMR, ¹H NMR, IR, and XPS spectroscopies. The paper discusses the catalytic surface composition, the effect of temperature, contact time, hydrogen partial pressure and benzene in the feed. The study demonstrated that the effect of Pt, hydrogen and benzene is crucial to orient the reaction toward naphthenes production.     

t-Butylation of 1,2-dihydroxybenzene over acidic zeolites

t-Butylation of 1,2-dihydroxybenzene (DHB) with isobutene as alkylating agent was carried out over various acidic zeolites such as USH-Y, H-beta, and H-ZSM-5. USH-Y zeolite exhibits the highest catalytic activity and considerable selectivity of 4-t-butylcatechol (4-TBC). The selectivity of 4-TBC is increased in the order of H-ZSM-5>USH-YH-beta. 3-t-Butylcatechol (3-TBC) is well produced over catalyst with high SiO₂/Al₂O₃ ratio and large pore aperture. 3,5-Di-t-butylcatechol (3,5-DTBC) selectivity is maximum in zeolite which contains strong acidity and large pore channel. The influences of various reaction parameters such as reaction temperature, space velocity, reactant molar ratio are discussed. In order to improve 4-TBC formation and decrease in 3,5-DTBC selectivity simultaneously, USH-Y zeolite was silylated by tetraethylorthosilicate (TEOS) resulting in the decrease of 3,5-DTBC selectivity over modified catalysts by about 25%. USH-Y zeolite shows high stability in the t-butylation for at least 350 h. The coke formed during the reaction was identified by FT-IR and the USH-Y zeolite could be regenerated through oxidative thermal treatment.     

双功能受阻胺光稳定剂的合成、表征及性能评价

以2,4-二羟基二苯甲酮、氯乙酰氯、2,2,6,6-四甲基哌啶胺等为主要原料,经两步亲核取代反应,合成了一种双功能受阻胺光稳定剂。目标产物结构经¹H NMR、¹³C NMR、FT-IR和ESI-HRMS分析进行了确认,并对其进行抗老化性能测试,结果表明其具备良好的防止聚合物光老化的性能。     

固体核磁共振在膦酸基质子交换膜中的应用

综述了固体核磁共振(NMR)技术的特点及其在燃料电池用膦酸基质子交换膜分析研究中的应用,重点介绍了运用¹H、³¹P、²⁹Si固体NMR以及¹H、³¹P变温固体NMR技术表征膦酸基质子交换膜的化学结构、氢键网络和质子传导机理等方面的研究进展。该综述表明固体NMR技术是一种研究膦酸基质子交换膜中氢键网络以及局部质子移动性的有效手段,并能进一步探索其质子传导的机理,为固体NMR技术在其他类型质子交换膜研究中的应用给予借鉴,为质子交换膜结构的表征提供一种新的方法。     

Synthesis and properties of tetrathiafulvalene-porphyrin assemblies

Two donor-σ-acceptor molecular systems incorporating tetrathiafulvalene (TTF) and tetraphenylporphyrin (TPP) units, TTF-TPP (dyad 1) and TTF-TPP-TTF (triad 2), were synthesized. Both dyad 1 and triad 2 and their synthetic intermediates have been characterized by ¹H nuclear magnetic resonance (¹H NMR) and mass spectrography (MS). Their ultraviolet and visible spectroscopy (UV-Vis) and cyclic voltammetry (CV) showed negligible intramolecular charge transfer interaction in their ground states. Their fluorescence intensity was strongly quenched compared with TPP, which implied the photoinduced electron transfer occurred from the TTF unit to the TPP unit in the excited state. On the other hand, their fluorescence intensity could be modulated by sequential oxidation of the TTF unit using chemical methods, which exhibited their potential application in fluorescence molecular switch.     

Synthesis and characterization of the layered sodium silicate ilerite

A sodium ilerite, molar ratios 1Na₂O:8.2SiO₂:10.2H₂O, was obtained with a good crystalline structure and characterized by several NMR techniques in addition to X-ray diffraction (XRD). The X-ray pattern of the as-synthesized ilerite is in very good agreement with the structure proposed by Gies and coworkers. The narrow ²⁹Si MAS NMR signals (FWHM=0.3 ppm) indicate a good short-range order of the framework. The proton dynamics influences several ²⁹Si NMR parameters. The 16 ppm signal in the ¹H MAS NMR spectra is explained by a proton in a bridging position in the short (2.3 Å) O4–O4 bonding. The quadrupole coupling constant C_qcc=100 kHz with η=0.2 for the 16 ppm signal, which was obtained from the ²H MAS NMR spectra, confirms this explanation. ¹⁷O NMR shows also a separate signal for SiOH groups but cannot resolve the three expected lines for SiOSi. PFG NMR detects a small mobile portion of water in the ilerite, which is located probably on the external surface of the crystallites. An intracrystalline diffusion coefficient of the intercalated water molecules of the order of magnitude 10⁻¹⁵ m² s⁻¹ was obtained by NMR tracer exchange experiments.     

苯并噻唑基修饰的开链Cu2+比色探针的合成及性能

以N-苯基二乙醇胺和2-巯基苯并噻唑为原料通过亲核取代反应合成了一种新型的苯并噻唑基修饰的开链冠醚类化合物1,并用核磁共振氢谱, 核磁共振碳谱及元素分析方法对合成产物进行了表征。利用紫外光谱仪考察了化合物1与多种金属离子（Mn²⁺、Co²⁺、Cu²⁺、Zn²⁺、Ni²⁺ 、Fe³⁺、 Hg²⁺、Cr³⁺、Al³⁺）在乙腈溶液中的光谱变化,并探究了化合物1处理过的滤纸条在水溶液中对金属离子的识别效果,通过核磁共振氢谱讨论了化合物1与金属离子形成配合物的作用机理。实验发现,化合物1的乙腈溶液中添加Cu²⁺后溶液颜色变为棕色,明显区别于添加其他离子;在水溶液中,特制的滤纸条遇到Cu²⁺会呈现黄色,而遇其他离子均无颜色变化。结果表明,化合物1仅对Cu²⁺具有选择性,且能通过裸眼进行识别,是一种高效、简便的Cu²⁺探针。     

二芳基二硫醚与硝基芳烃的反应

以二芳基二硫醚（ArSSAr）和硝基芳烃（ArNO₂）为原料,在廉价易得的甲醛次硫酸氢钠（Rongalite^®）和碳酸钾（K₂CO₃）共同促进下,以二甲亚砜（DMSO）为溶剂,50℃下合成了一系列非对称二芳基硫醚衍生物,产物结构经¹H NMR和¹³C NMR确证。该方法具有反应条件温和、原料易得和操作简单等优点。     

Iodosulfuron degradation by TiO2 photocatalysis: Kinetic and reactional pathway investigations

The photocatalytic degradation of a sulfonylurea herbicide, iodosulfuron methyl ester (IOME), has been studied in TiO₂ aqueous suspensions under UV irradiation. The influence of various parameters such as initial concentration, TiO₂ concentration and light intensity on the kinetic process was investigated. Disappearance rate of iodosulfuron followed pseudo-first order kinetics. A special attention was devoted to the identification of intermediates, using a new analytical approach which consists of coupling HPLC–DAD (UV), HPLC–ESI-MS and HPLC–¹H NMR techniques after a SPE pre-concentration step. By combining UV, MS and NMR data, up to 20 degradation products were unambiguously identified. Furthermore, ¹H NMR data allowed the differentiation of several positional isomers, in particular those of hydroxylation resulting from the attack of OH radicals on the benzene ring of IOME. Kinetic evolution profiles of main intermediates, end products (NO₃⁻, NH₄⁺, SO₄²⁻) and total organic carbon (TOC) were also examined in detail. From obtained kinetic and analytical results, the presence of privileged sites for the attack of OH radicals was shown and a detailed degradation pathway was proposed.     

Two-dimensional n.m.r. characterization of cycloaliphatic epoxy resins

The cycloaliphatic epoxy resins were studied by various two-dimensional nuclear magnetic resonance (2D n.m.r.) spectroscopies. The ¹³C n.m.r. spectra of the epoxy resins were assigned by using DEPT and 2D INADEQUATE techniques and the ¹H n.m.r. spectra were assigned by using 2D ¹H---¹H and ¹H---¹³C COSY techniques. Complete characterization of the samples synthesized by the oxidation of cyclohexene derivatives not only revealed the existence of the stereochemical isomers resulting from the structural difference of the oxide rings in the samples but also provided the composition ratio of the isomers.     

铜吡啶配合物催化合成1-甲氧基-2,2,6,6-四甲基哌啶-4-醇

目前1-烷氧基-2,2,6,6-四甲基哌啶基化合物的合成主要是以醛酮法为主。醇法合成虽然醇价格便宜,但合成效率很低。为解决这一问题,本文对醇法合成工艺进行了深入探讨,并以乙醇和4-羟基-2,2,6,6-四甲基哌啶氮氧自由基（ZJ-701）为原料,30%过氧化氢为氧化剂,氯化铜和吡啶配合物为催化剂,通过氧化和自由基偶合合成了1-甲氧基-2,2,6,6-四甲基哌啶-4-醇,通过红外光谱、核磁共振谱和质谱表征了其结构。通过实验进一步优化了反应时间、温度等一系列合成条件。研究结果表明：当反应时间为12h,反应温度为78℃,n(ZJ-701)∶n(乙醇)∶n(H₂O₂)∶n(CuCl₂)∶n(吡啶)=1∶39.25∶17.01∶0.034∶0.36时,产品产率最高,为60.6%,质量分数为98.8%,熔点为87～90℃。该方法具有原料乙醇便宜易得、反应条件温和、产品提纯容易等优点。