聚全氟三嗪高温弹性体的核磁共振

含氟高温弹性体是六十年代发展的一项新材料。利用碘代氟烷与全氟环丙醚生成碘代全氟醚,最后生成2,4-二(ω-碘六氟丙基)-6-七氟丙基-s-三嗪和2,4-二(ω-碘双氧全氟烷基)-6-六氟丙基-s-三嗪,结构式分别为Ⅰ和Ⅱ。利用~(19)F核磁共振谱鉴定其结构。     

全氟卤代烷在氯磺酸中的电化学反应

本文报道了以氯磺酸钾为电解质, 铂为电极, 进行氯磺酸的阳极氧化, 产生过氧二磺酰氯, 并和阳极池内α,ω-氯磺含氟烷进行反应, 生成相应的氯磺酸酯, 反应主要副产物为α,ω-二氯全氟烷, 在阳极有大量氢气逸出, 并得到碘。     

一种含氟丙烯酸树脂的制备及其表面疏水性

在聚合反应的后期阶段,向体系中引入含氟丙烯酸酯单体全氟辛基-(N-乙基-N-丙烯酸乙酯基)磺酰胺(QG-F814)共聚改性的方法制备了一种含氟丙烯酸树脂.接触角测定表明,该树脂具有良好的疏水性能.热重分析表明,该树脂在改性前后的耐热稳定性差别不大.     

ω-(2＇-甲基二氯硅乙基)—3-氧杂多氟烷基磺酰氟和ω-(2＇-甲基二甲氧基硅乙基)-3-氧杂多氟烷基磺酰氟的合成与聚合

长链含氟烷基磺酸盐作为表面活性剂已有不少报道,ω-三甲基硅取代的烷基磺酸盐作为表面活性剂也已有报道.本文报遭新的氟硅磺酸衍生物4,5,该类化合物可以水解聚合成以有机硅为主链的含氟聚磺酸盐表面活性剂,也可以和含羟基的载体如玻璃粉等化学键合而附着在载体上,然后水解磺酰氟基团成磺酸或磺酸盐.该类表面活性剂具有较好的溶解度和低表面张力. 我们以ω-碘-3-氧杂全氟烷基磺酰氟(1)为原料,与乙烯加成得化合物2,将2用三乙胺脱碘化氢得到ω-乙烯基-3-氧杂多氟烷基磺酰氟(3),3与甲基二氯硅烷经铂氯酸催化加成得到ω-(2′-甲基二氯硅乙基)-3-氧杂多氟烷基磺酰氟(4),4与甲醇、吡啶反应得化合物5,反应过程如下:     

全氟和多氟烷基磺酸的研究——Ⅻ.ω-碘-3-氧杂全氟烷磺酰氟的自由基加成反应

前已报道ω-碘-3-氧杂全氟烷磺酰氟(1a～c)与乙烯的自由基加成反应。我们发现用过氧化叔丁基、偶氮二异丁腈、过氧化苯甲酰为引发剂,均能使1与烯丙醇、乙酸烯丙酯、烯丙基乙基醚、正辛烯-[1]、丙炔醇顺利地进行加成,得到加成物2～6.1a,b与苯反应,用过氧化叔丁基引发的转化率低、产物较复杂。只有在约等摩尔过氧化苯甲酰时,才     

带功能基的全氟烷基乙烯基醚的研究——4.四氟乙烯与全氟-3,6-二氧杂-4-甲基-△~7-辛基磺酰氟溶液共聚反应单体竞聚率的测定

在乙烯-四氟乙烯溶液共聚合体系研究中,我们曾编制了一个简易的计算机程序,用于测定二种单体的共聚竞聚率,这一方法计算方便,而且可以避免原先作图法中的误差,结果较为可靠。前文我们报道了四氟乙烯与两个新的全氟烷基乙烯基醚的共聚合反应,并对其中一个新单体——7,7-二氯-3-氧杂-全氟庚烯-1——与四氟乙烯的共聚进行了单体竞聚率的测定。结果表明,这一新的含氟烯醚单体的聚合活性较其它已有报道的同类单体大。为了验证这一     

全氟和多氟烷基磺酸的研究 Ⅷ、N-(3′-三氯硅基丙基)-3-氧杂全氟烷基磺酰胺及其衍生物的合成

长链含氟烷基三氯硅烷及其衍生物的合成和性质已有不少报道,本文报道一类新的含氟磺酰胺基取代的硅烷衍生物的合成.这类化合物可作为无机硅酸盐材料的表面处理剂,由于含氟基团的引入,使被处理的物质具有氟碳表面的一些特性. 3-氧杂全氟烷基磺酰氟(1)和烯丙胺在三氟三氯乙烷(FC-113)中反应,得到对应的N-烯丙基取代的磺酰胺2;2与甲醇钠-碘甲烷反应,得到N-甲基-N-烯丙基取代的磺酰胺3.2和3分别与三氯硅烷在氯铂酸催化下反应,得到含氟磺酰胺基取代的三氯硅烷4     

具有共轭体系的酮类烯醇硅醚与全氟碘代烷的反应

应用连二亚硫酸钠的引发，通过全氟碘代烷与醛类，酮类烯醇硅醚的反应，合成α－全氟烷基羰基类化合物的方法。利用该方法，还可以用“一锅法”合成含氟β－二酮类化合物。本文报道了在类似的反应条件下，与苯环或双键共轭的烯醇硅醚和全氟碘代反应的结果。     

非茂钯催化剂催化乙烯/丙烯/ω-Cl-α-乙烯基单体三元共聚合的研究

本文探索了乙烯/丙烯/极性单体三元共聚物的合成方法.乙烯/丙烯/ω-Cl-α-乙烯基单体三元共聚物由于分子中引入了ω-Cl-α-乙烯基极性单体,改变了乙烯丙烯共聚物的化学惰性.我们采用催化剂Cat.L-Pd配位催化乙烯/丙烯/ω-Cl-α-乙烯基单体三元共聚合,合成了极性三元无规共聚物.探讨了催化剂结构、聚合条件对三元共聚合行为的影响,并优化了聚合条件.采用红外光谱(FTIR)、核磁共振碳谱(氢谱)(~(13)C(~1H)NMR)、示差扫描量热(DSC)和高温凝胶渗透色谱(GPC)等方法研究了共聚物的结构与性能.FTIR与~(13)C(~1H)NMR结果表明,催化剂Cat.L-Pd能够有效催化乙烯/丙烯/ω-Cl-α-乙烯基单体三元共聚合,共聚物中ω-氯代极性单体的插入量达3.6 mol%.极性单体不发生均聚合反应,但能够有效参与乙烯和丙烯的共聚合反应,形成三元无规共聚物.丙烯能够发生均聚合反应,但是不能形成聚丙烯长链段,主要发生乙烯与丙烯共聚合反应.乙烯最易发生聚合反应,并能够形成较长链段的聚乙烯.共聚物的Mw高于2×10~5g/mol.分子量分布在1.6～3.0,说明该类催化剂催化乙烯/丙烯/ω-Cl-α-乙烯基单体三元共聚合行为遵循单中心聚合机理.     

可见光诱导的共轭磺酰胺串联脱砜/环化反应

发展了一种可见光诱导的共轭磺酰胺串联脱砜/环化,合成全氟烷基化吲哚酮或α-芳基酰胺的方法。此反应以多氟烷基碘或溴为氟源,在发光二极管蓝光灯照射下,利用面式-三(2-苯基吡啶)合铱催化N-烷基-N-甲基丙烯酰基苯磺酰胺经过串联自由基加成/β-芳基迁移/脱砜环化过程,一步构筑两重碳-碳键,以41%~78%的产率合成了一系列含氟吲哚酮或α-芳基酰胺。此方法底物适用范围广,反应条件温和(室温),催化体系绿色,为具有潜在生理活性的含氟吲哚酮及α-芳基酰胺的合成提供了一条高效、快捷的新途径。     

Synthesis and Properties of Long-Chain Aromatic Telechelic Monodispersed Diols Radical-Initiated,Addition of 2-Mercaptoethanol onto α, ω Nonconjugated Dienes

Abstract

The synthesis of aromatic telechelic mono dispersed diols produced from the radical-initiated addition reaction of a twofold excess of 2-mercaptoethanol onto original α,ω nonconjugated dienes reaction is presented. These novel α,ω nonconjugated dienes were prepared by addition reaction of m-isopropyl α,α′dimethyl benzylisocyanate with mono dispersed telechelic diols obtained by fractionation of oligo(ethylene terephthalate)s. In these cases, the long chain α,ω diols were produced selectively and quantitatively. The products are soluble in most organic solvents in contrast to classical oligo (ethylene terephthlate)s and posses a lower glass transition and melting temperatures.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: Figures S1-S3.     

Enantioselective Nickel-Catalyzed Migratory Hydrocyanation of Nonconjugated Dienes

Metal-catalyzed chain-walking reactions have recently emerged as a powerful strategy to functionalize remote positions in organic molecules. However, a chain-walking protocol for nonconjugated dienes remains scarcely reported, and developments are currently ongoing. In this Communication, a nickel-catalyzed asymmetric hydrocyanation of nonconjugated dienes involving a chain-walking process is demonstrated. The reaction exhibits excellent regio- and chemoselectivity, and a wide range of substrates were tolerated, delivering the products in high yields and enantioselectivities. Deuterium-labeling experiments support the chain-walking process, which involves an iterative β-H elimination and reinsertion processes. Gram-scale synthesis, regioconvergent experiments, and downstream transformations gave further insights into the high potential of this transformation.     

Synthesis of Poly(Arylene Alkenylene)s by Pd‐Catalyzed Three‐Component Coupling Polycondensation of Diiodoarenes,Non‐Conjugated Dienes,and Nucleophiles that Involves Chain Walking Isomerization

The Pd‐catalyzed three‐component coupling polycondensation of diiodoarenes, nonconjugated dienes, and carbonucleophiles afforded poly(arylene alkenylene)s with moderate molecular weight in good yield. The reaction involves Mizoroki‐Heck coupling, olefin migration via chain walking, and addition of the carbonucleophile to the resulting π‐allylpalladium species. The polymerization with a slight excess of nucleophile with respect to diiodoarene also proceeded to give the polymer without significant decrease in molecular weight in spite of the nonstoichiometric mixture of the monomers. The Pd‐catalyzed three‐component coupling polycondensation of diiodoarenes, nonconjugated dienes, and diimide also proceeded. The base used in the reaction is critical for yield and molecular weight of the product. The reaction using NaHCO₃ afforded the product with low solubility, which can be explained by the high molecular weight of the polymer and/or the strong interaction of the electron donating dimethoxyphenylene groups and electron accepting diimide groups in the polymer. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 2535–2542     

How large is the conjugative stabilization of diynes?

The conjugation stabilization energies of dienes and diynes are considerably larger than estimates based on heat of hydrogenation differences between 1,3-butadiyne and 1-butyne as well as between 1,3-butadiene and 1-butene. Such comparisons do not take into account the counterbalancing hyperconjugative stabilization of the partially hydrogenated products by their ethyl groups. When alkyl hyperconjugation is considered, the conjugation stabilization of diynes ( approximately 9.3 kcal/mol) is found by two methods (involving isomerization of nonconjugated into conjugated isomers and heats of hydrogenation) to be larger than that of dienes ( approximately 8.2 kcal/mol).     

Factors influencing the autoxidation of fatty acids: effect of olefin geometry of the nonconjugated diene

Autoxidations of cis,cis, cis,trans, and trans,trans nonconjugated octadecadienoates and pentadecadienes were carried out in the presence of alpha-tocopherol to investigate the effect of olefin geometry on this oxidation process and provide insight into the factors that influence the autoxidation of fatty acids. We have found that as the trans character of the diene increases, the amount of O(2) trapping at the central (bis-allylic) position of the pentadienyl radical also increases. In addition, the rate constant for beta-fragmentation (k(beta) approximately 10(6) s(-1)) of the bis-allylic peroxyl radical decreased on going from the cis,cis to the trans,trans diene. We have also found that for the cis,trans nonconjugated dienes, there is a preference for trapping of the pentadienyl radical by O(2) at the transoid end, generating the cis,trans conjugated hydroperoxide as the major product.     

Crosslinked α-olefin-diene copolymers prepared using a metallocene catalyst deposited on the surface of SiO<Subscript>2</Subscript>-modified Fe<Subscript>3</Subscript>O<Subscript>4</Subscript>: Ferromagnetic oil sponges

The structure of zirconocene is determined experimentally. Zirconocene is found to catalyze effectively the copolymerization of α-olefins with nonconjugated dienes in the presence of minimal amounts of methylalumoxane as an organoaluminum activator. On the basis of a highly ferromagnetic carrier (a product of the reaction between Fe₃O₄ microparticles and Si(OEt)₄), a deposited zirconocene catalyst is obtained. Using the latter, copolymers of α-olefins (1-hexene, 1-octene, and 1-decene) with 1,7-octadiene and 1,4- di(3-butenyl)benzene are synthesized. The obtained ferromagnetic copolymers demonstrate properties of effective absorbents of hydrocarbons, namely, oil sponges. A copolymer of 1-octene and 1,4-di(3-butenyl) benzene is found to possess the maximum adsorption capacity (up to 8) in the studied series.     

The electrochemical fluorination of N-(ω-chloroalkyl)pipecolines and N-(ω-chloroalkyl)hexamethyleneimines

Electrochemical fluorinations of six kinds of N-(ω-chloroalkyl)pipecolines [N-(2-chloroethyl)-2-, N-(3-chloropropyl)-2-, N-(2-chloroethyl)-3-, N-(3-chloropropyl)-3-, N-(2-chloroethyl)4- and N-(3-chloropropyl)-4-pipecolines] and two kinds of N-(ω- chloroalkyl)-substituted hexamethyleneimines [N-(2-chloroethyl)- and N-(3-chloropropyl)hexamethyleneimines] were conducted. From these starting materials, corresponding chlorine-retained fully fluorinated amines together with ring isomerized products were formed in yields of 7.6～14.8% from the former and 5.4～5.5% from the latter, respectively. New chloropolyfluoroamines obtained in the present investigation have been isolated and characterized by spectroscopic (infrared, ¹⁹F nmr and mass) and elemental analysis.     

Synthesis of C-5 substituted nucleosides via palladium-catalyzed coupling of dienes and amines

The palladium-catalyzed coupling of C-5 iodopyrimidine nucleosides; 1,2-, 1,3-, or 1,ω-dienes; and amines provides a novel and efficient method for the preparation of a wide variety of C-5 aminoalkyl-substituted nucleosides. Adding certain Lewis acids, particularly zinc salts, improves the yields significantly. Secondary amines are the most effective amines for this process. Acyclic and cyclic dienes have been successfully employed. Protection of the 3′- and 5′-hydroxyl groups of iodouridine is required in order to obtain good yields when the coupling process is carried out on 1,3-dienes or long chain or branched non-conjugated dienes.     

Stereospecific 1,4-cis-hydrogenation of conjugated dienes,dienynes, and dienediynes catalyzed by chromium carbonyl complexes in stereocontrolled syntheses of physiologically active olefins

Synthesis of insect pheromones provides a good illustration of versatility, flexiblility, and practical convenience of the chromium carbonyl complexes-mediated 1,4-cis-hydrogenation of conjugated dienes as the tool for for stereocontrolled construction of di-, tri-, and tetrasubstituted olefins and nonconjugated dienes. A new strategy for synthesizing homoconjugated all-Z-dienes and trienes by hydrogenation of diene-alkyne conjugated systems using the same catalysts is proposed.     

Selective initiation of nonconjugated dienes containing electron donor–electron acceptor systems. III. Synthesis of vinyl ether–styrene monomers

In a continuation of our studies on nonconjugated dienes containing electron donor–electron acceptor systems which may function as model crosslinking monomers, we here report the synthesis of the series, 2-, 3-, and 4-(2-vinyloxyethoxy)styrenes. The dipole moments μ, infrared and ultraviolet absorption properties, refractive indices n_D³⁰, molar refractions (MR_D), and optical exaltations of the compounds were determined. In order to establish whether any intramolecular electronic interactions, e.g., intramolecular charge-transfer complexes, contribute to the structure and properties of these compounds, 2- and 4-(2-ethoxyethoxy)styrenes were also prepared, and their properties compared with those of the vinyloxy series. While there are differences in certain of the properties of these two groups of monomers, these differences are not sufficiently large to permit definite correlations with the proposed interactions.