简介：Anisodinewassynthesizedfrom3α-hydroxy-6β-acetyltropinein11steps.Laevorotaryisomerofanisodinewaspreparedfromtheasymmetricdihydroxylationofcompound10viatheosmiumcatalyzedprocessemployingp-chlorobenzoyldihydroquinidineasthechiralligands.

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简介：Thisarticlesummarizestheachievementsoftheauthors'groupintheareaofbiocatalyst-catalyzedorganicreactionsinrecent10years.AstrainofGeotrichumsp.obtainedbyscreeninuiscapableofstereoselectlvelyreducinganumberofcarbonylcompounds.Inmanycases,thestermghemistryiscomplementarywiththatobtainedbybaker'syeast.Therefore,thismicroorganismprovidesausefulpathwaytothepreparationofalcoholeompoundswithspecificconfigurations.Ontheotherhand,anmmberofplantsoureeshavebeenscreenedforoxynitrilasesandthehydrocyanationreactionsofvariousarylcarboxalde-hydeshavebeeninvestigated.A'micro-aqueousreactionsystem'wasinvented,bywhichaserlesofnovelopticallyactivecyanohydrinswereprepared.Onthishasis,ahighthrough-putcomtimasousreactionsystemhasbeendesigned.Thispaperalsodeseribesexamplesofthesynthesesofbio-activecompoundsbyusingtheoptieallyactivecompoundsobtainedfromtheabovementionedcatalyticreactionsasprecursors.

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简介：抗抑郁剂duloxetine(1)经由3-(dimethylamino)的不对称的转移加氢被准备-1-(thiophen-2-yl)propan-1-one(3)。Ru(II)，坚牢酸性蓝RH(III)和红外(III)几chiralligands的建筑群作为催化剂被检验并且(S，S)-N-tosyl-1,2-diphenyl乙烯肼(TsDPEN)Ru(II)建筑群被发现提供好产量和优秀enantioselectivity。

简介：ThesupportedRh-DIOPcomplexeswerepreparedthroughfunctionalizationofseveralmacroporouspolystyreneresinsndwereevaluatedbythehydrogenationofacetamidocinnamicacidinEtOH.Theporeeffectofthematrixeswasdiscussed.

简介：Asymmetrichydrisilylationcatalyzedbypolymericthiazolidinerhodiumcatalystswasconducted.Almostthesameopticalyieldshavebeenobtainedwhencomb-shapedpolymericligandsandtheircorrespondingmonomercomplexedrhodiumcataltystswereusedtoasymmetrichydrosilylationofacetophenone.Opticalyieldofchiral1-methylbenzylalcoholreachesashighas71.5%.Temperaturedependenceofenantioselectivehydrosilylationofacetophenonewasdiscussed.

简介：Stochasticresonance(SR)phenomenonofthesystemthatissubjecttotheasymmetrictwo-statenoiseisinvestigatedfromthebroadsense.Itisshownthattheamplitudesoftheoutputsignalexhibitthenon-monotonicdependenceontheinputsignalfrequencyω,andtheparametersdescribingtheasymmetrictwo-statenoise,suchasthetransitionrateλ,theorderparameterkdescribingtheasymmetricdegreeofthetwo-statenoise,andthenoisestrengthD.

简介：Thephenomenonofstochasticresonance(SR)inabistablenonlinearsystemisstudiedwhenthesystemisdrivenbytheasymmetricpotentialandadditiveGaussiancolorednoise.Usingtheunifiedcolorednoiseapproximationmethod,theadditiveGaussiancolorednoisecanbesimplifiedtoadditiveGaussianwhitenoise.Thesignal-to-noiseratio(SNR)iscalculatedaccordingtothegeneralizedtwo-statetheory(shownin[H.S.WioandS.Bouzat,BrazilianJ.Phys.29(1999)136]).WefindthattheSNRincreaseswiththeproximityofatozero.Inaddition,thecorrelationtimeτbetweentheadditiveGaussiancolorednoiseisalsoaningredienttoimproveSR.TheshorterthecorrelationtimeτbetweentheGaussianadditivecolorednoiseis,thehigherofthepeakvalueofSNR.

简介：Theasymmetricalkylationsofchiraltransitionmetalcomplexesderivedfrom(+)-camphorand2-aminomethyl-6-methylpyridinewereexaminedundermildconditions.Theformationofthecomplexes2isconductivetotheenhancementofdi-astereoselectivityinthealkylationsatroomtemperature.

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简介：一个周期的游戏系统的co进化的动力学为三种与不均匀的率在一个二维的方形的格子被调查。与混合得好的系统，共存和扑灭不同，在系统或者出现一零一个“行为为一种小人口尺寸是柔韧的，而，系统被共存为一张大人口支配一个。我们详细关于变化学习影响到状态的变化，并且发现关于变化和平均紧张的最大的振幅之间的差别决定系统最终是哪个状态。另外，我们介绍Potts精力解释原因零一个“行为。平均Potts精力每地点是距离到，这被显示出零一个“在模型的行为。

简介：Eleven(S)-(-)-bishydrocarbyl-(1-alkanoylpyrrolidin-2-yl)-methanolderivativesofthreetypesweresynthesizedfromL-proline,asymmtricallyselectivealkylationproductswereobtainedbyLDAtreatmentandalkylationusingmethyl2-bromoethylether,andthreetypesofchiralα-substituted-γ-butyrolactoneswereobtainedbyhydrolyzingthealkylationproducts,with%e.e.beingupto89percent.

简介：Introduction.Poly(N-vinylcarbazole)(PVCZ)hasreceivedmuchattentionasarepresentativephotoconductivepolymerandextensivestudiesonmechanical,physical,chemicalandelectricalpropertieshavebeenreported'’.Ingeneral,thePVCZobtainedbyradicalandordinarycanonpolym...

简介：AC2-symmetricalaryldiphosphitederivedfromchiralbinaphtholwaspreparedanditsrhodiumcomplexwasusedascatalystsintheasymmetrichydroformylationofolefins.Highcatalyticactivityandgoodregioselectivitywereobserved.Upto31.2%eeand38.1%eewereachievedforthehydroformylationof4-fluoro-styreneandvinylacetaterespectively.Theinfluencesofligand-to-metalratio,reactiontemperatureandthepressureofsyn-gasontheenantioselectivityandregioselectivitywerealsostudied.

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简介：Areusablecinchonaalkaloidderivativeligand,whichcouldbeeasilysynthesizedbytwosteptransformationwithcheap3,6-dichloropyridazineandquinineasmaterials,wasappliedtohomogeneousasymmetricdihydroxylationofolefinswithNMOasco-oxidantinMe2CO-H20systemandtheproductscouldbeextractedwithEt2Ofromtherecyclablecatalystsystem.80%---93%yieldand51%-99%eehavebeenobtained.Whentrans-stilbenewaschosenasthesubstrateforrecyclingexperiment,88%-92%yieldand>99%eehavebeenobtainedfortenrecycles.

简介：Theefiectsofmicroscopicthree-bodyforcesontheequatioilofstate(EOS)andthesingleparticlepropertiesofisospinasymmetricnuclearmatterhavebeenstudiedwithinBrueckner-Hartree-Fockframework~[1]Themicroscopicthree-bodyforcemodelconstructedfrommesonexchangecurrentapproachinRef.~[2]hasbeenextendedtoisospinasymmetricnuclearmatter

简介：新奇不对称的alkylaminoborazine单体，2-propylamino-4,6-bis(methylamino)borazine，第一次，并且直接被综合给melt-spinnablepolyborazine(PBN)的polymerized。这不对称的alkylaminoborazine被2,4,6-trichloroborazine(TCB)的aminolysis反应在温和条件下面与不同的胺综合。这条线路结果比常规线路便宜得多、简单。化学作文，结构，分子的重量和陶器的产量被EA，FTIR，NMR，GPC和TG分析调查。PBN为融化旋转展出合适的rheological性质，它建议它是为BN纤维的一位潜在的先锋。