New monoterpene phenyl ethers from Illicium micranthum

Seven new monoterpene phenyl ethers,namely micranthumnins A-G(1-7),were isolated from the stem bark of Illicium micranthum(Illiciaceae).Their structures were elucidated by comprehensive spectroscopic analyses including MS,IR,1D and 2D NMR.All compounds were evaluated for their anti-AChE activities.

A QSRR Study on the Relative Retention Time of Halogenated Methyl-phenyl Ethers

Halogenated methyl-phenyl ethers （anisoles） are ubiquitous organic compounds in the environment. In the present study, geometrical optimization and electrostatic potential calculations have been performed for 42 halogenated anisoles at the HF/6-31 G^＊ level. A number of statistically based parameters have been obtained. By multiple regression method, linear relationships between the gas-chromatographic relative retention time （RRT） and structural descriptors have been established for the training set of 32 halogenated anisoles. The result showed that the parameters derived from electrostatic potentials （ESPs） together with the molecular volume （Vmc） could be well used to express the quantitative structure-RRT relationships of halogenated anisoles. The best two-variable regression model gives a correlation coefficient of 0.980 and a standard deviation of 0.07, and the leave-one-out cross-validated correlation coefficient is 0.975. The goodness of the model has been further validated through exploring the predictive power for the testing set of 10 halogenated anisoles.

A Facile One-pot Method for the Synthesis of Vinyl Ethers from 2-Hydroxyalkyl Phenyl Selenides

A mild, one-pot procedure for the synthesis of vinyl ethers in good yields from 2-hydroxyalkyl phenyl selenides with primary or secondary organic halides has been developed.

Theoretical Analysis of Mass Transfer with Chemical Reaction Using Absorption of Carbon Dioxide into Phenyl Glycidyl Ether Solution

Theoretical analysis corresponding to the diffusion and reaction kinetics in a chemical reaction between carbon dioxide and phenyl glycidyl ether solution is presented. Analytical expressions pertaining to the concentration of carbon dioxide (CO2), phenyl glycidyl ether solution (PGE) and flux are obtained in terms of reaction rate constants. In this paper, a powerful analytical method, called the Adomian decomposition method (ADM) is used to obtain approximate analytical solutions for nonlinear differential equations. Furthermore, in this work the numerical simulation of the problem is also reported using Scilab/Matlab program. An agreement between analytical and numerical results is noted.

Using multiple site-directed modification of epoxide hydrolase to significantly improve its enantioselectivity in hydrolysis of rac-glycidyl phenyl ether

The epoxide hydrolase gene(SpEH) from Sphingomonas sp. HXN-200 was synthesized and expressed in robust Escherichia coli cells that had a dual protection system. The enantioselectivity(E-value) of the recombinant SpEH was 7.7 and the yield of the remaining(R)-PGE was 24.3% for the hydrolysis of racemic phenyl glycidyl ether(rac-PGE). To improve the catalytic properties of SpEH, the site-directed mutagenesis was carried out based on homology modeling, sequence alignment and molecular docking. Six residues(V195, V196, F218,N226, Q312, and M332) near the active site were mutated to hydrophobic amino acids and the positive mutations were selected for combinatorial mutation. The optimal mutant SpEH^(V196A/N226A/M332A) had an enhanced E-value of 21.2 and a specific activity of 4.57 U·mg^-1-wet cells, which were 2.8-, and 2.3-fold higher than those of wild-type SpEH. The optimal temperature and p H for purified Sp EHV196 A/N226 A/M332 Ato catalyze the hydrolysis of rac-PGE were 25 ℃ and 7.0 with 200 U·mg^-1. The enantioselectivity and yield of the remaining(R)-PGE of E. coliSpEH^(V196A/N226A/M332A)increased from 7.7 to 21.2 and 24.3% to 40.9%, respectively. The molecular docking and kinetic parameter analyses showed that SpEH^(V196A/N226A/M332A) has a greater affinity toward(S)-PGE than(R)-PGE, and that it was more difficult for the O-atom of ASP170 to achieve the nucleophilic attack on the Cα of(R)-PGE, resulting in its improved enantioselectivity.

Synthesis and Characterization of a Novel Copoly(aryl ether ketone) Containing 4, 4'-Biphenyl-bis[4-phthalazin-1(2H)-one] Moiety

A new monomer of 4, 4-biphenyl-bis[4-phthalazin-1(2H)-one] was synthesized from biphenyl and phthalic anhydride, and a novel copoly(aryl ether ketone) (PPEK) was synthesized from 2, 2-bis(4-hydroxyphenyl)-propane (BPA), 4, 4'-biphenyl-bis-[4-phthalazin-1(2H)-one], 4, 4- difluorodiphenylketone (DFK). The monomer and copolymer were characterized by FT-IR and 1H-NMR. DSC and TGA were used to the novel polymer.

Formation of Hybrid Ring Structure of Cyanurate/Isocyanurate in the Reaction be-tween 2,4,6-Tris(4-Phenyl-Phenoxy)-1, 3,5-Triazine and Phenyl Glycidyl Ether

Reaction products of 2,4,6-tris(4-phenyl-phenoxy)-1,3,5-triazine derived from 4-phenylphenol cyanate ester and phenyl glycidyl ether were analyzed. In addition to an isocyanurate compound and an oxazolidone compound which were well known as reaction products of cyanate esters and epoxy resins, compounds with hybrid ring structure of cyanurate/isocyanurate were determined. Gibbs free energies of the compound having hybrid ring structure of cyanurate/isocyanurate with two isocyanurate moiety were found to be lower than that of the compound with cyanurate ring structure through calculations. Calculation data supported the existence of hybrid ring structure of cy-anurate/isocyanurate. It was revealed that isomerization from cyanurate to isocyanurate occurs via hybrid ring structure of cyanurate/isocyanurate in the reaction of aryl cyanurate and epoxy.

Detection of Claisen Rearrangement Occurring in Allyl Phenyl Ether by in situ GC/MS

We report here a new strategy for revealing the Claisen rearrangement of allyl phenyl ether occurring in the gas phase by in situ GC/MS technique. The Claisen rearrangement has been observed when allyl phenyl ether passed through the capillary column at certain temperatures. The relative proportion of rearrangement products is dependent on the temperature of the capillary column and the substituents on the phenyl ring.

Synthesis and Adsorption Property of Two Polymeric Adsorbents with Pendent Ether Bonds

Two polymeric adsorbents, poly(methyl p-vinylbenzyl ether) and poly(phenyl p-vinylbenzyl ether), were synthesized from chloromethylated polystyrene. Their adsorption property for phenol in hexane solution was investigated. The results showed that the two adsorbents adsorb phenol from hexane solution through hydrogen-bonding and π-π stacking interaction.

STRUCTURE AND PROPERTIES OF PHOSPHROUS-CONTAINING POLY(ARYLETHER KETONE)WITH BISPHENOL-A MOIETY

A phosphrous-containing poly（aryl ether ketone） was synthesized derived from bisphenol-A and bis[4-（4- fluorobenzoyl）phenyl] phenyl phosphine oxide （FPPPO） by nucleophilic substitution reaction. The structure of the polymer was characterized by FT-IR, ^1H-NMR and ^31p-NMR. The thermal property of the PAEK was measured by DSC and TGA. The glass transition temperature （Tg） of the polymer was 205℃, and the 5% weight loss temperature under nitrogen was 475℃. Good solubility of the polymer in organic solvents, such as N-methylpyrrolidone, dimethylformamide, dimethylacetamide, dimethylsulfoxide and chloroalkanes was observed, flexible film was obtained from the polymer＇s CH2Cl2 solution. The limiting oxygen index （LOI） of the PAEK was 40, which indicated that organic phosphorus moiety can offer good flame retardant property to the polymer.

HFBAPP/6FDA/BPADA含氟苯醚型聚酰亚胺薄膜的制备与性能研究

以2,2-双[4-(4-氨基苯氧基)苯基]六氟丙烷(HFBAPP)为二胺单体,2,2′-双(3,4-二羧酸)六氟丙烷二酐(6FDA)和双酚A型二醚二酐(BPADA)为二酐单体制备了一系列HFBAPP/6FDA/BPADA含氟苯醚型PI薄膜。通过改变二酐单体比例,分析比较醚键与三氟甲基对PI薄膜综合性能的影响。结果表明:随着三氟甲基含量的升高和醚键含量的降低,HFBAPP/6FDA/BPADA含氟苯醚型PI薄膜的光学性能和热学性能提高,而力学性能下降,玻璃化转变温度最高可达247.3℃,800℃时的残炭率最高可达56.3%,可见光范围内的透光率最高可达88.2%,拉伸强度最高可达84.7 MPa。

聚乙二醇催化合成正丁基苯基醚

以乙醇为溶剂 ,聚乙二醇为相转移催化剂 ,氢氧化钾为碱 ,从正丁基溴和苯酚合成了正丁基苯基醚。当 0 1mol苯酚 ,0 3mol正丁基溴 ,乙醇为溶剂 ,在氢氧化钾和聚乙二醇 40 0存在下 ,加热 2h正丁基苯基醚收率达 96 7%

离子液体中正丁基苯基醚的绿色合成方法

制备了1-甲基-3-正丁基咪唑氟硼酸盐([bmim]BF_4)和N-正丁基吡啶氟硼酸盐([bpy]BF_4)两种离子液体,并作为溶剂和催化剂用于正丁基苯基醚的合成。考察了反应条件对正丁基苯基醚产率的影响,探讨了正丁基苯基醚的合成反应机理。在反应条件为65℃、2 h、氯代正丁烷与苯酚钠摩尔比为1∶1.2、离子液体与反应物的质量比为2∶1时,分别以[bmim]BF_4、[bpy]BF_4和混合离子液体([bmim]BF_4和[bpy]BF_4的摩尔比为1∶1)为溶剂和催化剂时,正丁基苯基醚的产率分别为80.2%、85.1%和96.9%。结果表明,混合离子液体因提高了与极性相异反应物的相溶性而明显提高了正丁基苯基醚的产率,并且具有良好的重复使用性能。

相转移催化合成正丁基苯基醚

相转移催化剂是一种良好的催化剂 .评述了由聚乙二醇、季铵盐、三乙醇胺、聚氯乙烯固载聚乙二醇树脂、聚苯乙烯固载季铵盐树脂、聚苯乙烯固载吡啶树脂、聚苯乙烯固载多乙烯多胺树脂、聚苯乙烯固载三乙醇胺树脂、聚苯乙烯固载二乙醇胺树脂、聚氯乙烯固载多乙烯多胺树脂催化合成正丁基苯基醚的方法和高分子相转移催化剂的重复使用性能 .

聚苯乙烯三乙醇胺树脂催化合成正丁基苯基醚

研究了聚苯乙烯三乙醇胺树脂催化合成正丁基苯基醚,考察了反应物摩尔比、反应温度、反应时间、催化剂用量等对产品收率的影响及催化剂重复使用性能。在本实验优化条件下,产品收率可达99％。催化剂回收和重复使用5次后,活性未下降,质量未损失。

苯醚1,2-亚乙基硅橡胶与常用硅橡胶的性能比较

在相同配方、相同工艺条件下比较了甲基乙烯基硅橡胶、低苯基硅橡胶、中苯基硅橡胶和苯醚1,2-亚乙基硅橡胶的常温力学性能、300℃下热氧老化性能、70℃湿热老化性能和耐辐照性能。结果表明,苯醚1,2-亚乙基硅橡胶的常温力学性能、耐湿热老化性能、耐辐照性能最佳,而耐300℃的热氧老化性能最差;中苯基硅橡胶的常温力学性能较差,但具有最优的300℃热氧老化性能;低苯基硅橡胶的湿热老化性能最差。

可自交联超支化聚醚醚酮的合成与热性能研究

Fluoro-terminated hyperbranched（poly（aryl） ether ketone）（HPOP-PEEK-F） with 4-phenoxyphenyl side groups was prepared from A2（2-（4-phenoxyphenyl）-1,4-diphenol） and B3（1,3,5-tris[4-（4-flourobenzoyl） phenoxy]benzene） with a function group ratio of 0.48:1（A2:B3）.The chemical structure of HPOP-PEEK-F was confirmed by FTIR and（）1H-NMR.The degree of branching（DB） of HPOP-PEEK-F was 0.66 determined by（）1H-NMR measurements.The phenyl ethynyl-terminated hyperbranched poly（ether ether ketone）（HPOP-PEEK-PEP） was prepared by the end-capping approach.The HPOP-PEEK-PEP showed high glass transition temperature than HPOP-PEEK-F,but exhibited lower thermal stability.After cross-linking,the glass transition temperature,thermal stability and anti-chemical corrodibility of HPOP-PEEK-PEP were all improved.

改性聚苯醚(MPPO)工程塑料国内外发展现状

综述了聚苯醚、共混改性聚苯醚、相容剂改性聚苯醚、热固性聚苯醚和阻燃聚苯醚工程塑料的国内外进展。介绍了其在工程塑料领域的消费量和消费分布以及在覆铜板中的应用。