邻硝基苯基荧光酮化学发光性能和机理研究

研究了在碱性介质中金属离子催化邻硝基苯基荧光酮（ｏ－ＮＰＦ）－Ｈ２Ｏ２体系的化学发光行为。结果表明，在研究的２０多种金属离子中，只有Ｃｏ２＋离子对ｏ－ＮＰＦ－Ｈ２Ｏ２体系有较强的催化发光作用，Ｃｏ２＋的浓度与发光强度在２．５×１０－９～３．０×１０－６ｇ／ｍＬ范围内呈良好的线性关系。通过对化学发光光谱、荧光光谱的研究以及用Ｈｕｃｋｅｌ分子轨道法（ＨＭＯ）计算了ｏ－ＮＰＦ的π电子分布和键级，提出了ｏ－ＮＰＦ可能的化学发光机理．     

THE PEROXIDASE/OXIDASE ACTIVITY OF SOYBEAN LIPOXYGENASE – II. TRIPLET CARBONYLS AND RED PHOTOEMISSION DURING POLYUNSATURATED FATTY ACID AND GLUTATHIONE OXIDATION

During the aerobic reaction of soybean lipoxygenase with polyunsaturated fatty acids (linoleic, linolenic, and arachidonic acid) oxygen uptake is followed by excited carbonyl photoemission. The chemiluminescence yield of phi cl = 10(-10) photons/O2 molecule consumed is enhanced 2-3 orders of magnitude by the carbonyl sensitizers 9,10-dibromo-anthracene-2-sulfonate (kET tau 0 = 10(4) M-1; phi cl = 10(-8) photons/O2) and chlorophyll-a (kET tau 0 = 10(6) M-1; phi cl = 10(-7) photons/O2), respectively. alpha,beta-Saturated triplet excited carbonyls as from 1,2-dioxetane cleavage are discussed to arise from a secondary peroxidase/oxidase reaction with aldehydes formed in the course of enzymic lipid peroxidation. When 1 mM glutathione is added to the aerobic lipoxygenase/arachidonate reaction, carbonyl emission (375-455 nm) is replaced by intense red bands (630-645 nm and 695-715 nm) resembling the characteristic spectrum of (1 delta g)O2-singlet oxygen dimol-emission. The quantum yield (phi cl = 10(-8) photons/O2) remains unaffected by chlorophyll indicating that the red emission is independent of excited carbonyls. The effect of GSH is attributed to dioxetane interception and subsequent glutathione peroxidation generating 1O2 by electron transfer from the superoxide anion radical to a peroxysulfenyl radical.     

原位产生的SO42-配位的二维无机钴配合物K2[Co3(OH)2(SO4)3(H2O)2]的水热合成及晶体结构

相同的水热反应条件下4-氨基-二(2-吡啶基)-1,2,4-三氮唑(abpt)、KSCN与钴盐(CoCl2·6H2O)反应合成了2种新的钴配合物:零维的单核配合物[CoSCN(abpt)](1α)和二维的无机层状配合物K2[Co3(OH)2(SO4)3(H2O)2](1β),并通过元素分析和红外光谱对其进行了表征.配合物1α的晶体属于单斜晶系,P21/c空间群.配合物1β晶体属于正交晶系,Cmc21空间群.在配合物1α中,abpt和SCN-配体都参与配位与Co(Ⅱ)离子形成了2个不同的单核单元,这些单核单元又通过S原子和N原子之间的氢键作用连成了三维超分子结构;在配合物1β中,abpt配体没有参与配位,而SCN-配体则被氧化成了SO42-离子并与Co(Ⅱ)离子配位形成了二维配位层状结构,相邻层之间进一步通过氢键作用形成了沿c轴方向有孔道的三维超分子网络,这些孔道里面填充着反离子K+.     

由异烟酰胺基间苯二甲酸根构筑的混核钴铕配位聚合物的合成、晶体结构及荧光性质

由水热法合成了一个混核金属配位聚合物{[CoEu₂(INAIP)₄(H₂O)₆]·2.5H₂O}_n(1)(INAIP^2-=异烟酰胺基间苯二甲酸根),并对其进行了元素分析、IR及X-射线衍射法表征。晶体结构研究表明：配合物1属于三斜晶系,P1 空间群。配合物1是由配体异烟酰胺基间苯二甲酸连接而成的二维双层状结构,该二维层通过氢键拓展为三维超分子结构。配合物1的荧光测试研究表明它具有典型的稀土铕离子红色荧光。     

2,4-二氯苯氧基乙酸的光转化化学发光机理研究

实验发现,2,4-二氯苯氧基乙酸(2,4-D)经紫外光转化后与KMnO4在H2SO4介质中反应可产生化学发光。采用液相色谱-质谱联用技术(LC-MS)对2,4-D光降解产物进行分析,推断光降解主要生成了多酚类降解产物,如2-氯对苯二酚(CHQ)和4-氯邻苯二酚等。化学发光光谱研究发现,2,4-D经紫外光转化后,与KMnO4反应的发光波长为690 nm,与2,4-D的典型降解产物CHQ的化学发光光谱一致。此发光现象是氧化还原过程中生成的Mn?吸收反应所释放出的化学能成为激发态,再返回基态时产生的特征辐射峰。该反应体系可用于2,4-D的检测,当2,4-D浓度在0.01～10 mg/L范围内与发光强度呈良好的线性关系;检出限为3.0μg/L。     

Synthesis, Crystal Structure and Luminescence Property of [Co(hmz)2(H2O)4]·2H2O

A new mononuclear Co(Ⅱ) complex, [Co(hmz)2(H2O)4]·2H2O, has been synthesized by the reaction of Co(CH3COO)2·4H2O with 1-(4-hydroxyphenyl)-5-mercaptotetrazole (Hhmz). It crystallizes in the monoclinic system, space group P21/n with a = 13.502(5), b = 6.718(3), c = 13.972(6) (A), β = 117.532(4)°, V = 1123.9(8) (A)3, Z = 2, M r = 553.45, F(000) = 570, Dc = 1.635 g/cm3, μ = 1.008 mm-1, the final R = 0.0272 and wR = 0.0684 for 2194 observed reflections (Ⅰ＞ 2σ(Ⅰ)). The Co(Ⅱ) is six-coordinated by two nitrogen atoms from two hmz-1 ligands and four water molecules, forming an octahedral geometry. The intermolecular hydrogen bonding and offset-panel π-π stacking interactions between the adjacent molecules extend the compound into a three- dimensional supramolecular framework. The title compound emits strong blue fluorescent light (λem(max) = 427 nm) at room temperature and is red-shifted compared with free ligand Hhmz (λem(max) = 342 nm).     

Chemiluminescence accompanied by the reaction of gold nanoparticles with potassium permanganate

It was found that potassium permanganate (KMnO(4)) could react with gold nanoparticles in a strong acid medium to generate particle size-dependent chemiluminescence (CL). For gold nanoparticles with the size of 2.6 or 6.0 nm, the reaction was fast and could produce the excited state Mn(II) with light emission around 640 nm. For gold nanoparticles larger than 6.0 nm, no light emission was observed due to a much slower reaction rate. The CL intensity was found to increase linearly with the concentration of 2.6 nm gold nanoparticles. The effects of the acid medium, concentration of KMnO(4) and presence of N(2) and O(2) were investigated. UV-Vis absorption spectra and X-ray photoelectron spectra (XPS) measured before and after the CL reaction were analyzed. A CL mechanism has been proposed suggesting that the potassium permanganate was reduced by gold nanoparticles in the strong acid medium to the excited state Mn(II), yielding light emission. The results bestow new light on the size-dependent chemical reactivities of the gold nanoparticles and on nanoparticle-induced chemiluminescence. The CL reaction was considered to be of potential use for bioanalysis applications.     

基于5-甲基-3-吡唑甲酸为配体的钴(Ⅱ)、镍(Ⅱ)配合物的合成、晶体结构和电化学性质

利用5-甲基-3-吡唑甲酸、咪唑和相应醋酸盐在乙醇和水混合溶剂中反应,得到了配合物[M(MPA)2(Im)2].2H2O(1:M=Co;2:M=Ni)(HMPA=5-甲基-3-吡唑甲酸,Im=咪唑)。用元素分析、红外光谱、X-单晶衍射结构分析、热重分析、循环伏安等对其进行了表征。配合物1和2的晶体结构参数如下:配合物1和2的晶体都属于单斜晶系,空间群为P21/n。配合物1的晶胞参数为a=0.847 02(16)nm,b=1.461 5(3)nm,c=0.899 67(17)nm,β=101.759(6)°,V=1.090 3(4)nm3,Z=2;配合物2的晶胞参数为a=0.853 59(6)nm,b=1.451 77(9)nm,c=0.889 83(6)nm,β=102.382 0(10)°,V=1.077 04(12)nm3,Z=2。金属离子与来自2个5-甲基-3-吡唑甲酸配体中的2个氮原子及2个氧原子,2个咪唑分子中的2个氮原子配位,形成八面体配位构型。配合物中的独立结构单元[M(MPA)2(Im)2].2H2O通过2种分子间氢键(N-H…O和C-H…O)形成三维超分子。循环伏安性质测试表明配合物1和2的电解过程均为准可逆过程。     

The extra-weak chemiluminescence generated during oxidation of some tetracycline antibiotics. II. Peroxidation.

This study was undertaken to establish the mechanism of chemiluminescence during the oxidation reaction of tetracycline antibiotics in the presence of molecular oxygen and H2O2. The spectral distribution of chemiluminescence and fluorescence and the quantum yields of chemiluminescence were measured. The chemiluminescence spectrum measured with cut-off filters revealed one broad blue-green band and bands with maxima at 580, 640 and 700 nm. The bands at 580, 640 and 700 nm were similar to those observed for singlet molecular oxygen. The effect of superoxide radical, hydroxyl radical inhibitors, singlet oxygen quenchers and D2O as solvent on the light emission was also studied. The formation of singlet oxygen during the oxidation of the investigated tetracyclines was also checked using the spectrophotometric method based on the bleaching of p-nitrosodimethylaniline. A mechanism for the reactions generating electronically excited compounds is proposed.     

(Z)-1-[2-(二苯基碘化锡基)乙烯基]-1-环己醇的合成、晶体结构和性质

报道了标题化合物的合成、晶体结构及性质。该晶体属于单斜晶系，空间群为P2~1，晶胞参数a=0.9255(3)nm，b=1.0504(3)nm，c=1.0217(3)nm，β=100.99(2)°，V=0.9750nm^3，Z=2，D~c=1.790g/cm^3，R=0.025，晶体结构由直接法解出。标题化合物分子中的锡原子被配体的三个碳、一个碘和一个氧原子配位；配位原子是畸变的三角双锥构型；标题化合物具有与卤素发生取代反应而不发生加成反应的性质。     

3-羧基甲氧基-2-萘甲酸钴配合物的水热合成、晶体结构和电化学研究

标题化合物[Co(L)(H2O)]n是由Co(OAc)2.4H2O、3-羧基甲氧基-2-萘甲酸(H2L)、NaOH经水热反应得到。采用元素分析、IR及X-射线衍射法表征了该配合物。晶体结构表明:晶体属于单斜晶系,空间群P21,Flack参数值为0.026(13)。晶胞参数:a=0.505 87(7)nm,b=0.942 88(12)nm,c=1.234 03(16)nm,β=95.015(9)°,V=0.586 35(13)nm3,Z=2,Mr=321.14,Dc=1.819 g.cm-3,μ=1.487mm-1,F(000)=326,Rint=0.023 8,R1=0.022 8,wR2=0.053 2。配合物的中心钴离子是六配位稍变形的八面体结构,3-羧基甲氧基-2-萘甲酸将配合物桥联成二维层状结构。对配合物的电化学行为进行了研究。     

A novel chemiluminescent method for the determination of salicylic acid in bactericidal solutions

A new flow-injection procedure has been developed for the determination of salicylic acid based on the enhancement of the chemiluminescence from the cerium(IV)-Tween 20 reaction by salicylic acid in acidic medium. The method is simple, selective and sensitive with a detection limit of 2.5x10(-9) g mL(-1). It is applicable to the determination of salicylic acid in the concentration range of 4.0x10(-9)-1.1x10(-6) g mL(-1). The relative standard deviation (RSD) is 0.85% for 4.0x10(-7) g mL(-1) salicylic acid (n=11). The method has been successfully applied to the determination of salicylic acid in bactericidal solutions. Furthermore, it is suggested that light emission from cerium(IV)-Tween 20 reaction is probably because of the formation of singlet oxygen 1O2* and the emitter is excited oxygen molecular pairs O2(1delta(g))O2(1sigma(g)-).     

一维链状钴(Ⅱ)和锌(Ⅱ)配合物的合成及结构表征

本文以乙酰丙酮和1,4-二(邻氨基苯氧基)丁烷进行缩合得到Schiff碱配体L,再分别同CoCl2.6H2O和ZnCl2.4H2O进行配位反应,得到了2个配合物[CoLCl2]n(1)和[ZnLCl2]n(2),并用元素分析,FTIR和X-射线单晶衍射进行了表征。结果表明,配合物1和2属于异质同晶,均属于正交晶系,空间群均是Pna21。在化合物1和2中,每个Co(Ⅱ)和Zn(Ⅱ)的配位环境均为扭曲四面体,2个配合物中每个配体L通过其两臂乙酰丙酮亚胺单元的端基氧原子同2个金属离子配位桥联形成一维链结构。     

铈基与钴基Co3O4-CeO2氧载体上甲烷化学链转化特性: 产物选择性控制

采用水热法制备了Co₃O₄/CeO₂(x)[x为钴铈原子摩尔比n(Co):n(Ce)=6:49:1]和Ce_1-yCo_yO_2-δ(y=0.10.4)2个系列复合氧化物, 并表征了材料的物理化学性质, 考察了这些氧化物作为氧载体参与甲烷化学链转化(化学链燃烧和化学链部分氧化)的反应性能. 结果表明, 2类复合氧化物的甲烷反应活性均明显优于单一氧化物CeO₂或Co₃O₄, 但2类氧载体上的甲烷反应产物的选择性具有明显差异. Ce_1-yCo_yO_2-δ氧载体形成了Ce-Co-O固溶体, 储氧能力明显增强, 体相晶格氧迁移速率与甲烷活化速率匹配较好, 甲烷反应产物以CO和H₂的合成气为主, 有利于甲烷的化学链部分氧化. Co₃O₄/CeO₂(x)氧载体中CeO₂与Co₃O₄之间的相互作用改善了材料的储氧能力和氧化活性, 其与甲烷反应时主要生成CO₂, 有利于甲烷化学链燃烧. 连续性化学链循环实验表明, 2类氧载体均具有较好的再生性能和循环稳定性.     

(Z)-1-[2-(三苯基锡基)乙烯基]-1-茚满醇及其酯和卤代物的合成与表征

在氮气保护下,1-乙炔茚满醇与三苯基氢化锡进行游离基加成反应,获得加成物(Z)-1-[2-(三苯基锡基)乙烯基]-1-茚满醇(1);将加成物(1)与苯酐反应,得到新型邻苯二甲酸单酯有机锡衍生物(2);衍生物(2)分别与二丁基氧化锡和三苯基氧化锡进行脱水反应,分别获得两个新型邻苯二甲酸酯的有机锡衍生物(3)和(4).将加成物(1)与卤素反应后,与锡原子直接相连的苯基被取代,得到一卤代和二卤代物(5～10).通过元素分析、¹HNMR和IR等手段对化合物1～10进行了结构表征,确定了该类邻苯二甲酸单酯和邻苯二甲酸酯的有机锡衍生物的结构.并测定了加成物(1)和一溴代物(6)的晶体结构,在加成物(1)中,由于分子内存在较弱的O→Sn[0.2778(8)nm]配位作用,锡原子呈扭曲三角双锥构型.在一溴代物(6)分子中,存在分子内O→Sn[0.2364(2)nm]配位键,锡原子呈扭曲的三角双锥构型.该系列化合物分子内的O→Sn配位能力和Lewis酸性强弱的顺序为:二卤化物>一卤化物>加成物;氯代物>溴代物>碘代物>加成物.     

Reaction CH(3) + OH Studied over the 294-714 K Temperature and 1-100 bar Pressure Ranges

Reaction of methyl radicals with hydroxyl radicals, CH(3) + OH → products (1) was studied using pulsed laser photolysis coupled to transient UV-vis absorption spectroscopy over the 294-714 K temperature and 1-100 bar pressure ranges (bath gas He). Methyl radicals were produced by photolysis of acetone at 193.3 nm. Hydroxyl radicals were generated in reaction of electronically excited oxygen atoms O((1)D), produced in the photolysis of N(2)O at 193.3 nm, with H(2)O. Temporal profiles of CH(3) were recorded via absorption at 216.4 nm using xenon arc lamp and a spectrograph; OH radicals were monitored via transient absorption of light from a dc discharge H(2)O/Ar low pressure resonance lamp at ca. 308 nm. The absolute intensity of the photolysis light inside the reactor was determined by an accurate in situ actinometry based on the ozone formation in the presence of molecular oxygen. The results of this study indicate that the rate constant of reaction 1 is pressure independent within the studied pressure and temperature ranges and has slight negative temperature dependence, k(1) = (1.20 ± 0.20) × 10(-10)(T/300)(-0.49) cm(3) molecule(-1) s(-1).     

Syntheses and Structures of Three Cobalt Metal-organic Frameworks with 3-（Sulfonyl-glycine）benzoic Acid

Three new coordination networks based on a versatile and unsymmetric building block 3-（sulfonyl-glycine）benzoic acid （HAL） ligand and inorganic Co（Ⅱ） salt, [Co（HL）（bipy）2]. ClO4·1.5H2O （1）, [Co3（L）2（H2O）6]·4H2O （2） and [Co（HL）（bpp）（H2O）2]·2H2O （3） （bipy = 2,2-bipyridine, bpp = 1,3-bi（4-pyridyl）propane）, have been synthesized in aqueous media and structurally characterized by single-crystal X-ray diffraction. Reaction of Co salt with H3L afforded a neutral 1D alternating chain, which shows a 3-D supramolecular network through hydrogen bonds. When the auxiliary 2,2-bipyridine is used, a mononuclear unit is constructed; if using auxiliary ligand bpp, a neutral 1-D uniform chain is obtained and further extended into a 3-D supramolecular structure through versatile hydrogen bonds. The H3L ligand in 1 adopts a bidentate chelating coordination mode while that in 2 and 3 assumes a pentadentate bridging and a bis-monodentate bridging modes, respectively. This work and our previous work evidently demonstrate that the structures vary with altering the second ligands.     

Development of FIA equipped with a chemiluminescence detector using a mixed reagent of luminol and 1,10-phenanthroline.

We developed an FIA system equipped with a chemiluminescence detector using a mixed chemiluminescence reagent of luminol and 1,10-phenanthroline for the detection of metal ions and metal complexes. The carrier, mixed chemiluminescence reagent comprising luminol, 1,10-phenanthroline, and cethyltrimethylammonium bromide, and H2O2 solutions were fed by corresponding pumps at a definite flow rate. Sample solutions dissolving hematin, [Co(NH3)4(H2O)2]2(SO4)3, CuSO4, NiCl2, K3[Fe(CN)6], and K4[Fe(CN)6] were analyzed as models by the means of the present FIA system. Solutions of hematin, [Co(NH3)4(H2O)2]2(SO4)3, CuSO4, and NiCl2 were detected as positive peaks, as usual. The order of the catalytic activity of these samples for the present chemiluminescence reaction using the mixed chemiluminescence reagent was [Co(NH3)4(H2O)2]2(SO4)3 > hematin > CuSO4 > NiCl2. On the other hand, sample solutions of K3[Fe(CN)6] and K4[Fe(CN)6] were detected as negative peaks and were determined over the ranges of 1 x 10(-8) - 1 x 10(-6) M with a detection limit of 1 x 10(-8) M and 2 x 10(-8) - 4 x 10(-6) M with a detection limit of 2 x 10(-8) M, respectively. Their negative peaks were observed reproducibly with a relative standard deviation of 2 - 5%.     

Oxygen cluster anions revisited: solvent-mediated dissociation of the core O4(-) anion

The electronic structure and photochemistry of the O(2n)(-)(H(2)O)(m), n = 1-6, m = 0-1 cluster anions is investigated at 532 nm using photoelectron imaging and photofragment mass-spectroscopy. The results indicate that both pure oxygen clusters and their hydrated counterparts with n ≥ 2 form an O(4)(-) core. Fragmentation of these clusters yields predominantly O(2)(-) and O(2)(-)·H(2)O anionic products, with the addition of O(4)(-) fragments for larger parent clusters. The fragment autodetachment patterns observed for O(6)(-) and larger O(2n)(-) species, as well as some of their hydrated counterparts, indicate that the corresponding O(2)(-) fragments are formed in excited vibrational states (v ≥ 4). Yet, surprisingly, the unsolvated O(4)(-) anion itself does not show fragment autodetachment at 532 nm. It is hypothesized that the vibrationally excited O(2)(-) is formed in the intra-cluster photodissociation of the O(4)(-) core anion via a charge-hopping electronic relaxation mechanism mediated by asymmetric solvation of the nascent photofragments: O(4)(-) → O(2)(-)(X(2)Π(g)) + O(2)(a(1)Δ(g)) → O(2)(X(3)Σ(g)(-)) + O(2)(-)(X(2)Π(g)). This process depends on the presence of solvent molecules and leads to vibrationally excited O(2)(-)(X(2)Π(g)) products.     

THE PEROXIDASE/OXIDASE ACTIVITY OF SOYBEAN LIPOXYGENASE - I. TRIPLET EXCITED CARBONYLS FROM THE REACTION WITH ISOBUTANAL AND THE EFFECT OF GLUTATHIONE

Soybean lipoxygenase shows a secondary peroxidase/oxidase activity: The aerobic reaction with isobutanal, enhanced by hydrogen peroxide as a cosubstrate, yields acetone, exhibits chemiluminescence and consumes oxygen (phi cl = 1.3 x 10(-9) photons/O2 molecule consumed). 9,10-Dibromoanthracene-2-sulfonate increases the photoemission (kET tau 0 = 2 x 10(4) M-1; phi cl = 0.9 x 10(-7) photons/O2), whereas it is diminished by sorbate, tryptophan, 2-methyl-1,4-naphthoquinone, glutathione, and superoxide dismutase. In the presence of hydrogen peroxide the lipoxygenase reaction with glutathione yields yet another excited state. From the well-known reactions promoted by horseradish-peroxidase, these features are concluded to indicate the novel activity of soybean lipoxygenase. With isobutanal as a substrate lipoxygenase acts as an oxidase and as a peroxidase. The mechanism suggested leads to photoemissive triplet excited acetone as expected from the cleavage of an intermediate dioxetane.