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Chem. Lett. Vol. 2006, 35, 628-629

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PhotochromismofDiarylethene-functionalizedPolystyrenewithHighConversioninaSolid-statePolymerFilm

SeiyaKobatakeÃandHirotsuguKurataniDepartmentofAppliedChemistry,GraduateSchoolofEngineering,OsakaCityUniversity,3-3-138Sugimoto,Sumiyoshi-ku,Osaka558-8585

(ReceivedMarch20,2006;CL-060337;E-mail:kobatake@a-chem.eng.osaka-cu.ac.jp)

Photochromicpolymersthatexhibitthermallyirreversibleandphotochemicallyreversiblecolorchangesweresynthesizedbyradicalpolymerizationofastyrenemonomerhavingaphoto-chromicdiarylethenechromophore.Thephotocolorationreac-tionofthepolymerproceededwithhighconversioneveninthesolid-statepolymerfilm.

Thermallyirreversiblephotochromiccompoundsarepoten-tiallyapplicableforopticalmemory,display,andswitchingde-vices.1,2Theuseofphotochromiccompoundsforsuchdevices

requirestorespondinhighsensitivityinasolidstate.Diaryl-ethenescanundergothermallyirreversibleandfatigueresistantphotochromicreactionseveninasolidstate.3–5Althoughvari-oustypesofphotochromicdiarylethenepolymershavebeensofarreported,6–18inmostcasesthephotocolorationreactioninthesolidfilmdoesnotreachtohighconversion.Diaryletheneshavetwostableconformations,antiparallelandparallelones.Theyareinequilibriumeachotherinsolution.19Thephoto-cyclizationreactioncanproceedonlyfromtheantiparallelcon-formation(Scheme1).Inthesolidstate,themaximumconver-siondependsonacontentoftheantiparallelconformationsiftheconformationsarefixed.Ifthethienylgroupsarerotatedinthepolymerfilm,aphotocolorationreactionisexpectedtoreachtohighconversioneveninsolid-statepolymerfilms.Someofdiaryletheneamorphousfilmshadhighphotochromicconver-sions.20,21Inthiswork,weexaminedphotochromicreactionsofpolystyrenehavingadiarylethenechromophore(Scheme2).Thediarylethenechromophoreinpolymer2awasfoundtoex-changebetweenreactiveantiparallelandnonreactiveparallelconformationsatroomtemperatureinthepolymerfilmevenbelowglass-transitiontemperature(Tg).Asaresult,thephoto-cyclizationreactionproceedswithhighconversioninasolid-statepolymerfilm.Suchpolymerscanexhibithighsensitivityforcolorationeveninthinfilms.Styrenemonomerhavingadiarylethenechromophore1awassynthesizedandcarefullypurifiedbyHPLCtogivecolor-lesscrystals(seeSupportingInformation).Themonomerwaspolymerizedbyaradicalpolymerization(seeSupportingInfor-mation).Thepolymerhadahighmolecularweight(Mn¼40;400)andapolydispersityof2.18.ThepolymerwassolubleinCHCl3,THF,andacetone,anditwasinsolubleinmethanol.Tgofthepolymerwasdeterminedtobe106󰀂C,whichissimilartothoseofpolystyreneandpoly(p-substitutedstyrene)s.22Photochromicbehaviorofpolymer2awasexaminedintol-uene.Uponirradiationwithultraviolet(UV)lightthesolutionturnedtoblue.Thebluecolorisduetotheformationoftheclosed-ringform.Figure1ashowsabsorptionspectralchangesuponphotoirradiation.Uponirradiationwith313-nmlight,anewabsorptionbandappearedat592nm.Theabsorptionbandincreasedinirradiationtimeshowinganisosbesticpointat313nm.Aftertheirradiationfor10min,thesolutionreachedinaphotostationarystate.Theblue-coloredsolutionwasbleach-edbyvisiblelightirradiation(󰀁>500nm).

Toexaminetheconversionfromtheopen-toclosed-ringformsofthediarylethenechromophore,1HNMRspectroscopywasemployed.Themethylprotonsin2aexistat1.85ppm.AfterirradiationwithUVlightforafewminutes,anewpeakappearedat2.08ppm,whichisassignedtothemethylprotonsinthe

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Figure1.Absorptionspectralchangesofdiarylethenepolymer2aintoluene(a)andinfilm(b)uponirradiationwith313-nmlight.

628ChemistryLettersVol.35,No.6(2006)CopyrightÓ2006TheChemicalSocietyofJapan

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化学键【精品】

化学键【精品】


Inorganic Chemistry
43(2004)
This paper makes an important contribution to the still sparse literature on the correlation of the topology of the energy along a reaction path and the associated changes in structure determined by the topology of the electron density. --- R.F.W. Bader
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水分子孤对电子伸展方位
（6）反应过程
计算量子化学研究室
量子拓扑分析理论方法的研究拓展
84年以来，先后在国际、国内重要理论化学 年以来，先后在国际、 年以来 刊物发表有关研究论文近百篇， 刊物发表有关研究论文近百篇，在国际上取得 了一定的影响，先后得到多项国家、 了一定的影响，先后得到多项国家、省自然科 学基金资助。 学基金资助。
化学键的新概念
R.F.W. Bader “Atoms in molecules: A quantum theory”.
水热法合成铁掺杂的硫化镉及光催化性能

水热法合成铁掺杂的硫化镉及光催化性能

水热法合成铁掺杂的硫化镉及光催化性能刘阳龙;郑玉婴;曹宁宁;王翔【摘要】以硝酸镉、硝酸铁和硫脲为原料,水为溶剂,通过水热法一步合成铁掺杂的硫化镉.产物经SEM,XRD,EDS和XPS等技术进行表征,以亚甲基蓝的光催化降解为目标反应,评价其光催化活性.结果表明:水热温度对硫化镉的形貌影响较大,不同反应温度可分别得到球状、花状、簇状和棒状的硫化镉,其中花状硫化镉的光催化性能最高.XRD分析表明,160℃反应时,所得掺铁的硫化镉均为六方晶体结构.光催化实验表明,铁掺杂能进一步提高硫化镉的催化活性,当Fe和Cd的掺杂比为1:10时,催化效果最佳.%Fe-doped cadmium sulfide was prepared by hydrothermal method in aqueous solution using cadmium nitrate,ferric nitrate and thiourea as raw materials.The samples were characterized by SEM,XRD,EDS and XPS.The photocatalytic degradation of methylene blue (MB)in aqueous solu-tion was used as a target reaction to evaluate their photocatalytic activity.The experimental results show that the reaction temperature has a great effect on the morphology of cadmium sulfide,and spherical,flowerlike,clustered and rodlike cadmium sulfide are obtained in various reaction tempera-tures.Among them,the photocatalytic activity of flowerlike CdS is observed to be better than other CdS materials.The XRD indicates that Fe-doped cadmium sulfide is hexagonal crystal structure when the reaction temperatu re is 160℃.The experimental results also indicate that Fe-doped can obviously improve the photocatalytic activity of cadmium sulfide and when the doping ratio of Fe to Cd is 1:10, the photocatalytic effect is the best of all.【期刊名称】《材料工程》【年(卷),期】2017(045)010【总页数】6页(P12-17)【关键词】硫化镉;水热法;形貌;铁掺杂;光催化【作者】刘阳龙;郑玉婴;曹宁宁;王翔【作者单位】福州大学石油化工学院,福州 350108;福州大学材料科学与工程学院,福州 350108;福州大学材料科学与工程学院,福州 350108;福州大学材料科学与工程学院,福州 350108【正文语种】中文【中图分类】O644Abstract： Fe-doped cadmium sulfide was prepared by hydrothermal method in aqueous solution using cadmium nitrate, ferric nitrate and thiourea as raw materials. The samples were characterized by SEM, XRD, EDS and XPS. The photocatalytic degradation of methylene blue (MB) in aqueous solution was used as a target reaction to evaluate their photocatalytic activity. The experimental results show that the reaction temperature has a great effect on the morphology of cadmium sulfide, and spherical, flowerlike, clustered and rodlike cadmium sulfide are obtained in various reaction temperatures. Among them, the photocatalytic activity of flowerlike CdS is observed to be better than other CdS materials. The XRD indicates that Fe-doped cadmium sulfide is hexagonal crystal structurewhen the reaction temperature is 160℃. The experimental results also indicate that Fe-doped can obviously improve the photocatalytic activity of cadmium sulfide and when the doping ratio of Fe to Cd is 1∶10, the photocatalytic effect is the best of all.Key words：CdS；hydrothermal method；morphology；iron doping；photocatalytic随着人类社会的快速发展，环境污染问题的日益严重，半导体光催化技术越来越受到人们的重视[1，2]。

烯烃复分解反应催化剂及其应用简介

烯烃复分解反应催化剂及其应用简介


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意义

打破了通常意义下碳碳双键化学惰性难以 改造的固有模式，并且可任意构造碳碳双 键。
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Lynn, D. M.; Kanoaka, S.; Grubbs, R. H. J. Am. Chem. Soc. 2001, 123, 3187-3193. Lynn, D. M.; Mohr, B.; Grubbs, R. H.; Henling, L. M.; Day, M. W. J. Am. Chem. Soc. 2000, 122, 6601-6609.
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Gallivan, J. P.; Jordan, J. P.; Grubbs, R. H. Tetrahedron Lett. 2005, 46, 2577-2580
第一个具有普适意义的催化剂

Grubbs小组于1992年报道了卡宾配位钌化合物。牺牲了部 分活性，但提高了选择性，耐氧，可在质子溶剂中使用。
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噻唑类化合物的活性研究_武文斌

噻唑类化合物的活性研究_武文斌

·医药论坛·噻唑类化合物的活性研究武文斌１，２郭元晖１，２＊韩晓璐１徐豫１程火刚１（１．第二军医大学研究生管理大队上海２００４３３；２．第二军医大学药学院上海２００４３３）摘要：噻唑类化合物作为一种重要的生物学活性支架，具有广泛而强有力的生物学活性。

本文着重突出阐述了最新噻唑类化合物的重要性，认为它具有十足的应用前景。

关键词：噻唑抗菌性抗癌性生物学活性中图分类号：Ｒ９６文献标识码：Ｂ文章编号：１６７２－８３５１（２０１２）０５－００７６－０２Thiazolidinone-A biologically active scaffoldWu Wenbin1，2Guo Yuanhui1，2*Han Xiaolu1Xu Yu1Cheng Huogang1（1.Administration of Postgraduates，Second Military Medical University，Shang Hai200433，China；2.Department of Organic Chemistry，School of Pharmacy，Second Military Medical University，Shang Hai200433）Abstract：The broad and potent activity of thiazolidinones has established it as one of the biologically important scaffolds.This article is an effort to highlight the importance of the thiazolidinones in the present context and promise they hold for the future.Key word：Thiazolidinones Antibacterial Anticancer Biological activity1引言有机医用化学的主要目的之一是设计分子的综合产物，使它具有与人类治疗因子相同的价值。