共查询到20条相似文献,搜索用时 312 毫秒
1.
Introduction Photoinducedelectrontransfer (PET)isoneofthemostinterestingfeaturesofdonor acceptorsystemsforthedesignandtheconstructionofartificialmoleculardevicesforenergyconversionandinformationprocessingwhichhaveanumberofpotentiallyintriguingapplicat… 相似文献
2.
IntroductionAxiallydissymmetric 1,1′ binaphthyland 1,1′ bi phenylligandsbearingtwoidenticalgroupsinthe 2 ,2′ positionhaveprovedtoberemarkablyusefulinenantiose lectivecatalysis ,withopticalyieldscloseto 10 0 %enan tiomericexcess (ee)obtainedinseveralpreparativelyim p… 相似文献
3.
IntroductionWiththefamousDIOPligand ,KaganintroducedtheimportantconceptofC2 symmetryinliganddesign .1However ,itisnotalwaystruethataC2 symmetricligandshouldnecessarilybesuperiortoanon symmetriccoun terpart .Transitionmetal catalyzedallylicalkylationviasymme… 相似文献
4.
催化酯化新进展(英) 总被引:1,自引:0,他引:1
酯化是一经典的有机合成反应,随着肽合成的进展,在此领域已做了大量的研究工作。介绍了一些新的酯化有机催化剂如: N , N ′ Dicycloh exylcarbodiim ide, 4dim ethylam in op yridin e, Bis[4( 2, 2dim ethyl1, 3dioxolyl)m ethy ] carbodiim ide, benzotriazolyl N oxytrisoim ethylam inophosphonium 和 2eth ox y1(eth oxycarbonyl)1,2dihydroqu inolin e。参考文献 20 篇。 相似文献
5.
IntroductionDesignandsynthesesofnovelsupramolecularcom plexeswithunusualandtailorablestructuresarefunda mentalstepsindiscoveryandfabricationofvarioustech nologicallyusefulfunctionalsupramoleculardevices .1 3Recently ,considerableeffortshavebeendevotedtocr… 相似文献
6.
Introduction Opticallyactivesecondaryalcoholsareusefulbuild ingblocksforpharmaceuticals ,agrochemicalsaswellasothermaterials .1Avarietyofasymmetriccatalyticreac tionshavebeendevelopedforpreparingsuchimportantsecondaryalcohols .2 Inadditiontostraightforwa… 相似文献
7.
Introduction 4 ,4′ Biisofraxidin (1) ,anewbiscoumarin ,1wasisolatedbyWanchaiDe Eknamkulandhisco workersfromtherootculturesofimpatiensbalsaminaL . (Bal saminaceae) ,whichhaslongbeenusedinThailandasatraditionalfolkmedicine .TheleavesofBalsaminaceaeareusuallyusedf… 相似文献
8.
0IntroductionNumerousuniqueframeworkshavebeenreportedbyassemblyofrationaldesignedorganiclig-andswithmetalionsoverthepastdecade1~3.Itisknownthatbothimidazoleandcarboxylatearefunctionalgroupsforcoordinationtotransitionmetalionstoformcomplexes4~6.Howeve… 相似文献
9.
SynthesisandQuantumChemistryStudiesof(R)┐N┐(Propionylthiazolidine┐2┐thione┐4┐methoxycarbonyl)germaniumSesquioxide*LIYe-zhi**,... 相似文献
10.
Introduction Non covalentinteractionshaveabiginfluenceontheconformationalorganizationofthebiomoleculeswhichisresponsiblefortheregio andstereo specificityofvariousbiologicalprocesses .1Amongtheseinteractions ,thein tramolecularstackinginteractionbetweens… 相似文献
11.
1INTRODUCTIONBis N,N’(dithiodi 2,1 phennylene)benzamidehasbeenwidelyusedinpro cesingofrubberaspeptizerforproducingfreeradical... 相似文献
12.
SynthesesandMagneticPropertiesofCu(Ⅱ)-RE(Ⅲ)HeterobinuclearComplexeswithN,N′-Bis(3-carboxyisalicylidene)-trimethylenediamineTA... 相似文献
13.
INTRODUCTIONThesynthesisofpolynuclearcopper lanthanoidcomplexesisofspecialinterestforsev eralreasons〔1-4〕.Thesecomplexesareim... 相似文献
14.
N,N,N′,N′-四丁基丙二酰胺萃取Yb(Ⅲ)的研究 总被引:1,自引:0,他引:1
取代酰胺类萃取剂易合成、分解产物易除去可用于萃取铀 (Ⅳ )、钍 (Ⅳ ) [1 - 4 ] ,但对高放废液中共存稀土元素的萃取研究较少[5] 。本文在以前研究工作的基础上[6] ,进一步探讨了TBMA萃取Yb(Ⅲ )的性能。1 实验部分1 1 试剂和仪器试剂均为AR级。TBMA由实验室合成 ,减压蒸馏提纯 ,经元素分析、红外光谱等检验产品为目标产物 ,纯度高于 98%。FTS 1 65红外光谱仪 (美国Bio Rad公司 ) ,75 2分光光度计 (上海分析仪器总厂 ) ,PHS 2C精密数显酸度计 (上海伟业仪器厂 ) ,恒温康氏振荡器 (实验室改装 )。1 2 实验准确称量 1 970 3g… 相似文献
15.
Study on the extraction and separation of rare earth with new extractants is important in the rare earth chemistry and nuclear reprocessing. In this work, the extraction of Ce(Ⅲ) with N,N,N′,N′-tetrabutylmalonamide (TBMA) in toluene from nitrate media has been investigated. The effect of the concentration of nitric acid, TBMA and salt-ing-out agent (LiNO3) and also the temperature on the distribution ratios was examined. The stoichiometries of the extracted complexes were determined to be Ce(NO3)3·3TBMA and Ce(NO3)3·4TBMA, respectively. The ap-parent extraction constants and the enthalpy of the extraction were calculated based on the extraction data, which are logKex1=3.97, logKex2=4.75 and ΔrHm?=-31.25kJ·mol-1, respectively. The IR spectra of the loaded organic phase supported the suggested extraction mechanism. 相似文献
16.
1 INTRODUCTIONCertaincoppercomplexeshavebeenshowntohaveunusualchemicalpropertiessuchasoxygentransfer,oxidativeadditionandhomogenouscatalytichydrogenation[1].Oxidativeadditionreactionsarekeystepsintheactivationofσbondsinagreatnumberofcatalyticprocess.Cop… 相似文献
17.
1INTRODUCTIONβ elemene,asesquiterpenoidcompound,isanaturalproductisolatedfromesen tialoilcontainedintherootandstemofChinesehe... 相似文献
18.
19.
IntroductionTheinteractionofbisphosphineswith (transition)metalsisafascinatingfieldfromthecoordinationchemist’spointofview .Awidearrayofmono andmulti metalliccis η2 P ,P′coordinatedcomplexesareformedinwhichavarietyofcoordinationmodesisen countered .Thechela… 相似文献