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1.
The nucleophilic substitution of the nitro group in 5-nitrobenzofurazan-3-oxide is studied undder soild-liquid phase-transfer catalysis (PTC) conditions.  相似文献   

2.
利用Gaussian-94计算程序中的B3LYP方法,在6—311 G(2d)6d基组下,对Si5,Si5H3,Si5H6,Si5Li3和Si5Na33原子簇的几何结构进行优化和频率计算.结果表明,Si5原子簇中最稳定的具有D3h对称性的结构中,位于同一平面上的3个Si原子确实具有剩余的成键能力,可以与3个H,Li,Na原子和6个H原子形成稳定的化合物.研究还发现,虽然H,Li和Na都属同一主族,但它们与Si5原子簇中Si原子的键连方式却不同,而且它们的加入,对Si5原子簇的“三角双锥”结构也有不同的影响.  相似文献   

3.
A new monomer, 3,9-diallyl-3, 9-dibenzyl-1, 5,7,11 - tetraoxa- spiro [5,5] undecane (6) was prepared by the reaction of 2- allyl- 2' - benzyl- propanediol - 1.3 with dibutyltin oxide, and then treated with CS_2. Monomer 4 could be initiated by cationic initiators to give a viscous polymer (white powder in the case of polymerization at 0℃). Upon the NMR and IR spectra of the obtained polymer, the components and their relative amount were estimated. The polymerization mechanism was discussed.  相似文献   

4.
5.
6.
The molecular structure of the previously reported compound [Mo(CO)3(η6-P3C3But3)] has been determined by a single-crystal X-ray diffraction study. Syntheses and molecular structures are also described for the structurally related compounds [Mo(CO)3(η5-P3C3But3)(Me)(Bun)], [Mo(CO)3(η5-P3C3But3)(H)(Bun)] and [Mo(CO)3(η4-P3C3But3(Me)(Bun)(H)(O)Li(THF)3]. Density functional calculations at the B3LYP/cc-pVDZ(-PP) and BP86/cc-pVDZ(-PP) levels have been carried out on the above complexes and the nature of the bonding between the different rings and molybdenum is discussed. 31P NMR spectroscopic evidence is presented for the existence of the novel complex [Mo(CO)3(η6-P3C3But3)PtCl2(PEt3)] in which the triphosphabenzene ring acts as an overall 8-electron donor to the two metal centres.  相似文献   

7.
3, 5-二氯苯胺的电化学合成   总被引:7,自引:0,他引:7  
以3, 5-二氯硝基苯为原料, 采用阴极转动分隔式电解槽, 在65℃、电流密度10A/dm^2、阴极转速400r/min和电极电位在-0.35~-0.45V范围的条件下进行电合成, 所得3, 5-二氯苯胺的产率达90%左右, m.p. 49~52℃。  相似文献   

8.
HormoneisaveryhoP0tatkindofbiol0glcalmolede,ltplaTharegulationro1einmetabelism.TheinterachoLofrareeothwithborm0nehasearelybeenreporteds0far[1'2J.lntheprerentwork,theinteraedonofrareearthwith3.5,3'-triiodothryor`ire(T.)wasstodiaibyusingNMRandPOtentiometrictitrationat37tandanionicstrenotofO'15mo1e/LNaC1,TheP0tenhometrictitrah0nwasperformedin1:1DMSO-H.O(vol1imeratio)usingthemethoddedndinprevi01ispeper[3].TheNMR8peaofsarnples(PH=4,to)wererecorded'onBrukerARX-4ooNMRSpeCtrometerusingT…  相似文献   

9.
Abstract: Ten novel 2-alkylthio-5-(3, 4, 5-tribenzyloxyphenyl)-1, 3, 4-oxadiazole derivatives (5a-j) were synthesized from methyl 3, 4, 5-trihydroxybenzoate by ethedfication, hydrazidation, cyclization and thioetherification reactions. The structures of 5a-j were confirmed by 1HNMR, MS spectra and elemental analysis. The results indicated that most of the compounds 5 exhibited good fungicidal activities. The activity of 5h is higher than 90% against Fusarium oxysporum and Botrytis cinereapers in 50 mg/L.  相似文献   

10.
1INTRoDUCT1oNThechemistriesofsamariumdiiodideandlow-valenttitaniumareofcurrentin--.terestinorganicSynthesis.Theyhavebeenwidelyusedinsyntheticreactions(l.2i.Thereactivityofthereagentstowardsvariousnitrogen-containingcomPOundshasal-readybeenexamined.Thereare,toourknowledge,noliteratureexamplesforthereductionofafylidenecyanoacetatederivativeswiththesereagents.Recently,wefoundthatthetitlecompoundisobtainedbycyclodimerizationreactionofpchlorObenzylidenecyanoacetatewithsamariumdiiodideorlow-va…  相似文献   

11.
New esters of 3β,5α,6β-trihydroxysteroids and 3β,5-dihydroxy-6-ketosteroids containing 6-chloropyridine groups characteristic of the alkaloid epibatidine were synthesized by acylation with 6-chloronicotinoylchloride. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 175-179, March-April, 2009.  相似文献   

12.
11NTRODUCT1ONWeattemptedtosynthesizeanextractant(1)bythereactionofadipylchloridewithcyclopentanonepiperidineenamineaccordingtoHunig'sprocedure"',however,wemainlyobtainedthetitlecompound,whichmaybepossiblyapotentialmedicinet2'3i.Itsmolecularstructurewasfinallyconfirmedbythesingle-crystalstructuredeterminationafterconventionalUV,IR,lHNMR,MSandelementana-lyticalworks.2EXPER1MENTALSECT1ON2.1SynthesisToastirredsolutioncontaining8Omlofchloroform,2.8mloftri-ethylamineand1.51g(O-Olmol)…  相似文献   

13.
Aliphatic polycarbonates and their copolymers have been used in drug controlled release system and other biomedical applications due to their good biocompatibility, favorable mechanical properties and some elasticity1, such as poly(1, 3-dioxan-2-one)2 and…  相似文献   

14.
Reactions of [CpRhCl2]2 (Cp = η5-C5Me5 (Cp*), η5-C5Me4Et (Cp′), η5-C5H3 t Bu2(Cp″)) with in situ generated H2Se give triangular [Cp3Rh3Se2]2+ clusters. These clusters were isolated as PF6 salts and characterized with ESI-MS, 77Se, 1H NMR and DFT calculations. [Cp3Rh3Se2] undergoes two reversible two-electron reduction steps. Quantum-chemical calculations reveal non-trivial bonding situation in the cluster core and changes in the hapticity of the Cp* ligand upon reduction. Crystal structure of [Cp 3 * Rh3Se2][Re2(μ-Cl)3(CO)6]Cl · 3.3H2O has been determined.  相似文献   

15.
Novel diarylethene derivatives: N-substituted-3,4-bisheteroaryl-2,5-dihydropyrroles were synthesized through Mcmurry couple reaction with high yields. The photochromic properties and UV-Vis absorption spectra were studied. The maximal absorptions of their close forms were around at 406 nm or 446 nm, which related mainly with heteroaryl groups but not with substituted groups at nitrogen atom of dihydropyrrole. The absorption of their colored form could be matched with blue light laser.  相似文献   

16.
本文用自洽场组态相互作用方法(SCF-CI)精确计算了次氯酸分子HOCl的振动激发态的能级以及次氯酸分子中的H和Cl分别被D和^3^7Cl取代后的HO^3^7Cl,DO^3^5Cl和DO^3^7Cl的同位素效应, 这些理论计算值与已有的实验结果吻合较好, 还预测了一些尚未观测到的谱线频率及同位素效应。  相似文献   

17.
New steroid derivatives containing 6-chloropyridine groups characteristic of the alkaloid epibatidine and neonicotinoid insecticides were synthesized by reacting 3β,5α,6β-trihydroxysteroids or 3β,5-dihydroxy-6ketosteroids with 2-chloro-5-chloromethylpyridine. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 180-182, March-April, 2009.  相似文献   

18.
以1,3,5-三羟基苯、新戊二醇、三氯氧磷等为原料,采用简洁、高效的合成路线,通过两步反应合成了新型阻燃剂1,3,5-三(5,5-二甲基-1,3-二氧杂己内磷酸酯基)苯.通过红外光谱、核磁共振氢谱、质谱、元素分析以及热失重分析等对产物结构和热性能进行了表征和研究.热失重分析表明:该阻燃剂起始分解温度为295.26℃ ,在295.26℃ ~343.38℃和350.40℃ ~578.04℃温区迅速炭化;当阻燃剂被加热到681.03℃时,炭残余量高达43.33 %.  相似文献   

19.
1mTRODUCT10NSincethetimeKaganhasdem0nstratedasimplepreparationofsamariumdiio-didefromsamariummetaland1,2-diiodoethanet1),SmI2hasbeenwidelyusedinsyntheticreactionst23.Thereactivityofsamariumdiiodidetowardsvariousnitrogen-containingcomP0undshasalreadybeenexamined.Thereare,toourknowledge,noliteratureexamplesforthereductionofcyanogrouptoproduceaminowiththisreagent.Inthispaper,wediscussedthecrystalstructureofthetitlecomP0undsyn-thesizedbythereactionofsamariumdii0didereagentwithp-chloroben-zyli…  相似文献   

20.
<正> INTRODUCTION. The crystal structures of potassium and ammonium 3,5-dinitramino-1,2,4-triazolate, which were synthesized by a new method, have been determined by X-ray structure analysis.  相似文献   

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