离子液体中卤代哒嗪氟代新方法的研究

在离子液体和氟化钾反应体系中，研究了卤代哒嗪化合物的氟代反应，讨论了微波辐射条件下由卤代哒嗪化合物合成氟代哒嗪化合物的方法。用离子液体作为反应介质替代了传统的分子溶剂，提高了产物收率，简化了操作。用微波反应不仅获得了较好的收率，也缩短了反应时间。利用离子液体和微波辐射条件进行氟代反应是一种绿色化学方法。     

氟代哒嗪的合成

氟代哒嗪是一类生物活性很强的化合物, 已被广泛应用于医药和农药等领域,本文提出进一步控索简便温和并具有高度选择性的氟代方法。     

4—氟—3,6—二氯哒嗪合成新方法

氟代哒嗪类化合物与有一定生理活性的氟代嘧啶类化合物有着同分异构的关系。而4-氟-3,6-二氯哒嗪又是合成其它药物的重要中间体。1984年田官荣报道了4-氟-3,6-二氯哒嗪的合成及同亲核试剂的反应性能和同类化合物     

4—氟—3—羟基—1—取代苯基—6—哒嗪酮类结构及其反应的研究

氟代马来酐和苯肼缩合,反应先在乙醚后在25％盐酸中进行。4-氟-3-羟基-1-苯基-6-哒嗪酮(Ⅰ)的收率达54％,文献仅26％。Ⅰ和吗啡啉反应,得熔点为243～244℃的白色晶体。熔点及元素分析结果(表1)表明,产物为4-吗啡啉基-3-羟基-1-苯基-6-哒嗪酮(Ⅱ),据此作者认为氟原子位于第4位。     

哒嗪酮苷类化合物的合成研究

一些嘧啶系列的苷具有较强的生理活性,其中5-氟脲苷是有效的抗癌药物。而哒嗪与嘧啶具有同分异构关系,那么,哒嗪苷类化合物是否也有相似的生理活性呢?六十年代初,Wagner等开展了这一领域的研究;到七十年代中期,Katz等合成了与天然     

哒嗪酮衍生物的合成和生物活性研究

合成了16个含哒嗪酮环新化合物, 所有化合物结构均通过¹H NMR, IR和元素分析确证. 生物活性初步研究结果表明, 在200 mg/kg浓度下, 化合物7a, 7b, 7c和7d对二龄家蝇幼虫具有较好的杀虫活性, 对三龄蝗蝻活性不明显.     

哒嗪酮衍生物的合成和生物活性研究

以4,5-二氯-3(2H)-哒嗪酮和2-溴-1-苯乙酮或2-溴-1-苯-1-丁酮反应合成了中间体4,5-二氯-2-(2-苯基-2-氧代-乙基))-3(2H)哒嗪酮,再与吗啉和哌啶反应合成了标题化合物.所有化学物的结构通过1 HNMR、IR和元素分析确证.初步生物活性测定表明,部分化合物在200mg·L-1对东方粘虫有一定的生物活性.     

甲基酮的二氟同系化-卤化反应:一锅法合成β-卤代-α,α-二氟代酮

以（溴二氟甲基）三甲基硅烷（TMSCF₂Br）为二氟卡宾源,利用其兼具TMS转移特性及自活化特性,仅在催化量的n-Bu₄NBr的催化启动下,直接完成甲基酮的烯醇化-二氟环丙烷化反应以及与卤正离子的开环卤化反应,并使用卤负离子作为卤源,采用其原位氧化形成卤正离子的方法实现了偕二氟环丙烷硅醚的开环-卤化,合成了β-卤代-α,α-二氟代酮类物质.     

芳氧基哒嗪氧基乳酸酯合成条件的研究－－3，6－二卤代哒嗪中卤原子对其亲核取代反应的影响

研究了芳氧基哒嗪氧基乳酸酯合成条件，发现可通过两种途径来合成。研究了 起始物中卤素原子对其亲核取代反应的影响。通过分子力学和量化计算，发现3， 6－二氟哒嗪在亲核取代反应中较其它3，6－二卤代哒嗪有优势，实验结果证实了 3，6－二氟哒嗪在温和的条件下合成了芳氧基哒嗪氧基乳酸酯。     

α-卤代酮的脱卤新方法

报道了一种以乙醇为溶剂,在锌粉和甲酸铵催化下的α-卤代酮的脱卤新方法。该体系也适用于α,α-二卤代酮和卤代苄的脱卤反应,产物结构结构经~1H NMR,IR和MS(ESI)确证。     

Methods of Fluorination in Organic Chemistry

Since the days of the “Manhattan Project” our knowledge of the chemistry of fluorine-con-taining compounds has increased tremendously. At first only considered out of curiosity, this area of research bordering between inorganic and organic chemistry has developed from modest beginnings to such a complexity of interesting ramifications that it would be very difficult to review all aspects in detail. The motivating force behind the developments in this field were, above all, the unusual properties the numerous compounds acquire on introduction of fluorine substituents. The spectrum of unusual modes of behavior extend from extreme stabilization in fluorine-containing polymers and blood-substitutes to drastic increases in reactivity in pharmacologically and phytomedicinally active substances and in dyes. Moreover, one physical peculiarity of the fluorine atom, its magnetic moment, opens a new route to the decyphering of metabolic processes.—Parallel to the ever increasing number of fluorinated compounds there has been a concomitant increase in the variety of methods of synthesis and reagents, which is frequently difficult to overview in entirety, even for the specialists. Older, simple methods such as halogen metathesis with metal fluorides and electrofluorination are being refined as far as higher selectivity is concerned, and completely new, very reactive substances such as hypofluorites and noble-gas fluorides enable fascinating reactions on complex substrates, e. g. steroids and nucleobases. The present review is an attempted documentation and classification of the methods as well as a critical appraisal, not least from the standpoint of efficiency and economic aspects.     

离子液体在氟化反应中的应用进展

离子液体作为一类新型绿色溶剂,具有制备简单、稳定性好、溶解能力强、挥发性小、安全性强等优点,因此在有机单元反应包括酯化、氧化、还原、重排反应等中的应用相当广泛,有着十分诱人的应用前景.虽然其在氟化反应中的应用研究开始得较晚,但发展很快,目前在重氮化氟化、亲核氟化、亲电氟化以及电化学氟化等方面都取得了较大的进展.本文综述了近年来离子液体在氟化反应中应用的最新进展情况,并对其未来发展方向和应用前景进行了展望.     

Effect of Fluorination on Aggregate Structure of Perylene Diimide

The effect of fluorination on the aggregate structure of a novel fluorinated perylene diimide, N, N‘-diperfluorophenyl-3, 4, 9, 10-perylenetetracarboxylic diimide 1, was investigated by UV-Vis absorptions and the conformation simulations from AM1 semi-empirical quantum mechanics modeling. The results showed that in the solid film 1 molecules stacked with the perfluorinated phenyl groups straightly over or below the perylene cores of the adjacent 1 molecules.     

Fluorination of carbinols with 2,2-difluoro-1,3-dimethylimidazolidine in ionic liquid

The utility of ionic liquids for fluorination using 2,2-difluoro-1,3-dimethylimidazolidine (DFI) is described. Further, the fluorination of chiral epoxyalcohols gave the chiral monofluoromethylated epoxides.     

活性氟化铝的制备及催化氟化性能

氟化铝是多相氟氯交换反应的催化剂或载体,在氟氯烃及其替代品的气固相合成中,氟化铝催化剂占了重要作用.据报道氟化铝晶体结构有αβ γεδηθκ等多种晶型[1],研究表明[2],稳定态的α型没有催化活性,β或γ型具有催化活性[3].用于电解铝助熔剂的工业氟化铝是稳定态的α型,不能用于催化剂或载体.因此活性氟化铝催化剂的制备一直是ODS替代品制造业的研究重心,也是含氟烃生产的技术核心.……     

Fluorination in superacids: a novel access to biologically active compounds

In HF-SbF₅, reaction of various alkaloids with NBS, NCS, H₂O₂ yields fluoroderivatives: anti-addition is observed at the C6C7 double bond with tabersonine, but a more complex reaction is operative with vindoline, leading to 7-substituted (Br, Cl, OH)-20-fluoro derivatives. A completely different reaction pathway is observed with bis indole alkaloids (vinblastine, anhydrovinblastine, vinorelbine) in HF-SbF₅. In the presence of NBS (or better of CCl₄ or CHCl₃), 20′,20′-difluoroderivatives are obtained. Vinflunine (20′,20′-difluoro-3′,4′-dihydrovinorelbine) has been selected for its promising antitumor activity.     

Lipophilicity Modulations by Fluorination Correlate with Membrane Partitioning

Bioactive compounds generally need to cross membranes to arrive at their site of action. The octanol-water partition coefficient (lipophilicity, logP_OW) has proven to be an excellent proxy for membrane permeability. In modern drug discovery, logP_OW and bioactivity are optimized simultaneously, for which fluorination is one of the relevant strategies. The question arises as to which extent the often subtle logP modifications resulting from different aliphatic fluorine-motif introductions also lead to concomitant membrane permeability changes, given the difference in molecular environment between octanol and (anisotropic) membranes. It was found that for a given compound class, there is excellent correlation between logP_OW values with the corresponding membrane molar partitioning coefficients (logK_p); a study enabled by novel solid-state ¹⁹F NMR MAS methodology using lipid vesicles. Our results show that the factors that cause modulation of octanol-water partition coefficients similarly affect membrane permeability.     

Rotational Spectra of 2,3,6-Trifluoropyridine: Effect of Fluorination on Ring Geometry

The ground state rotational spectrum of 2, 3, 6-trifluoropyridine has been investigated in the 2.0\begin{document}$ - $\end{document}20.0 GHz region by pulsed jet Fourier transform microwave spectroscopy. The experimental rotational constants are \begin{document}$ A $\end{document} = 3134.4479(2) MHz, \begin{document}$ B $\end{document} = 1346.79372(7) MHz, and \begin{document}$ C $\end{document} = 941.99495(6) MHz. The transitions are so intense that rotational transitions of all mono-\begin{document}$ ^{13} $\end{document}C and \begin{document}$ ^{15} $\end{document}N isotopologues are measured in natural abundance. The semi-experimental equilibrium rotational constants of the 7 isotopologues were derived by taking account of the anharmonic vibrational corrections, which allowed a semi-experimental determination of the equilibrium structure of 2, 3, 6-trifluoropyridine.     

氩氧控制气氛下直流电弧放电中氟化反应

本文以前文为基础测定了不同氟化剂存在下杂质元素的蒸发率,计算了弧温、电子密度以及杂质元素的电离度,研究了影响元素谱线强度的诸因素,用晶体X射线衍射分析了电极反应残留物,提出了氟化反应的机理,并通过热力学计算予以说明。 1实验部分 1.1 仪器及主要工作条件 HILGER WATTS大型棱镜摄谱仪,直流电弧光源,电流10