乳化结晶法制精蒽新工艺的研究

研究了用乳化结晶法从粗蒽制精蒽的新工艺，考察了溶剂种类、乳化剂种类、乳化剂用量、水／粗蒽质量比、助剂加入量以及结晶终温等因素对精蒽质量的收率的影响，实验结果表明：以糖醛作溶剂，米唑啉物Ｓｐａｎ２０复合型乳化剂，经一次乳化结晶得得精蒽纯度大于９５％，符合国家一级精蒽标准，蒽收率大于８０％。     

1,9—乙撑基蒽和1,9—乙撑基—10—甲基蒽的单电子氧化

报道了１，９－乙撑基蒽和１，９－乙撑基－１０－甲基蒽在ＣＨＣｌ３／定点 与碘反应的机理，它们的单电子氧化生成游离基正离子，该过程存在侧链去质子和吡啶进攻蒽环两种竞争反应，蒽环上引入乙撑基使侧链氧化远比环氧化占优势，乙撑基比甲基容易去质子。     

蒽在SDS/BA/H2O体系中的光谱特征

用紫外-可见吸收光谱和荧光发射光谱研究了蒽在不同组成和结构的十二烷基硫酸钠(SDS)/苯甲醇(BA)/H20微乳液中的光谱特征,探讨了微乳液组成和结构对蒽光谱特征的影响,阐述了蒽在微乳液中的定位。结果表明,蒽位于O/W微乳液的膜相和油核;在SDS/BA/H2O W/O微乳液中,蒽定位于油连续相。     

同步扫描-化学除氧胶束增稳室温燐光法同时测定痕量菲和荧蒽的研究

本文利用同步扫描-化学除氧胶束增稳室温燐光法研究了痕量菲和荧蒽的同时测定。考察了菲和荧蒽二元混合物中两组分的相互干扰限量。讨论了在胶束体系中菲和荧蒽相互干扰的机理。实验表明,适宜的△λ为186nm。菲和荧蒽的同步峰分别位于480nm和547nm。该法的线性范围为:菲为2.7×10~7～4×10~(-6)mol/L,荧蒽为2.2×10~(7-)～1×10~(-5)mol/L。检出限为:菲为2.7×10~7mol/L,荧蒽为2.2×10~(-7)mol/L。相对标准偏差小于3％。     

蒽镁的某些化学反应

本文报道了蒽镁与O_2,H_2,C_2H_2,CO,CO_2,(CH_3)_2CO,C_2H_5Br的反应。其中,蒽镁与(CH_3)_2CO和C_2H_5Br的反应可以分别作为合成(9,10-二氢-9-蒽基)二甲基甲醇和9,10-二乙基-9,10-二氢蒽的简易方法。     

导数恒基体强度同步荧光分析法同时测定光谱严重重叠的1-氯蒽和9-溴蒽

通过选择适合测定路径,应用恒基体强度同步及荧光法同时测定了两种光谱严重重叠的蒽衍生物1－氯蒽和9－溴蒽。混合物中1－氯蒽和9－溴蒽不必预分离就能直接同时测定。在混合物中1－氯蒽和9－溴蒽的回收率分别为83．5％－94．0％,90．0％－94．0％,检出限分别为0．69μg/L,10μg/L。     

三苯胺取代蒽衍生物的结构和光学性质

采用DFT/B3LYP,HF,CIS及TD-DFT方法在6-31G(d)水平上研究了4种三苯胺取代蒽衍生物的结构和光学性质.计算结果表明:苯基、萘基、蒽基和芘基在蒽环9位进行修饰对分子的电子结构和光学性质影响微小.激发态结构弛豫主要发生在蒽环的键长;HOMO能级值较高,-5.0～-5.2eV,分子易产生空穴;蒽环9位取代基共轭面增加时,吸收光谱和发射光谱发生轻微红移,且发射光谱位于蓝光区域,约440nm.这4种衍生物均具有潜能作为性能优良的空穴型材料或蓝色发光材料应用于有机发光二极管中.     

玻璃基质表面蒽的固定化及荧光光谱研究

在玻璃基质上,通过化学键和将蒽经二乙三胺固定到基质表面,制备了一种包含蒽传感元素的新型光诱导电子转移荧光薄膜。用接触角的测定、红外光谱和固定态蒽的稳定性对薄膜进行了表征。研究了固定态蒽的静态荧光光谱特性,干态和湿态下激发和发射光谱表明,其荧光发射的3个单体峰与典型的蒽单体发射基本一致,而在干态时较易形成激基缔合物。通过时间分辨荧光光谱和荧光寿命的测定,给出了固定态蒽的激发态光物理过程的模型。     

ClO2对溶液中蒽、芘和苯并[a]蒽的降解

多环芳烃是一类具有潜在致突变、致癌/助癌特性且在环境中较为稳定的微污染物. 采用高效液相色谱(HPLC)技术测定了ClO₂对溶液中蒽、芘和苯并[a]蒽的降解效果. 预备实验中发现ClO₂可在较短时间内有效去除这3种多环芳烃. 研究了反应时间、ClO₂浓度及pH对多环芳烃降解率的影响, 结果表明反应时间和ClO₂浓度可明显影响多环芳烃的降解率, 而pH在3.2~9.7范围内对其几乎没有影响. 当反应时间为30, 60, 120 min, ClO₂浓度为0.1, 0.4, 0.5 mmol·L^-1, pH为7.2时, 蒽、芘和苯并[a]蒽的降解率达到最大值, 分别为99.0%, 67.5% 和89.5%. 采用气相色谱-质谱 (GC-MS) 技术对ClO₂氧化蒽的反应产物进行了鉴定, 结果表明主要产物为生物降解性较强的9, 10-蒽醌. 通过分析蒽与ClO₂的反应特性, 在单电子转移理论的基础上, 对蒽与ClO₂的反应机理及可能的反应途径进行了讨论.     

以(S)-(-)-α-甲基苄胺为手性源的蒽类衍生物的合成

从10-羟甲基-9-蒽醛出发,经过Williamson醚化反应引入手性源(S)-(-)-α-甲基苄胺,合成了3个新的手性蒽类衍生物,其结构经NMR, MS和元素分析表征.     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.