联基
- 与 联基 相关的网络例句 [注:此内容来源于网络,仅供参考]
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Starting from 3-benzoyl-5-formyl-indolizine, 3-benzoyl-5-(2'2'-diacetylethenyl)-indolizines and analogs were obtained by the 〓mediated aldol condensation or Wittig reaction. These compounds,promoted by low-valent titanium, gave highly functionlizedcycl[3,2,2]azine derivatives. The coupling reaction proceeded betweenthe carbonyl group and the carbon-carbon double bond, a rare example inMcMurry reaction.
我们以3-苯甲酰基-5-甲酰基中氮茚为原料,通过三碘化钐促进的aldol反应和Wittig反应制备了3-羰基-5-羰基乙烯基中氮茚,随后经低价钛还原偶联,没有生成正常的分子内羰基-羰基偶联产物,而是得到反常的羰基与α,β-不饱羰基的双键偶联产物,较高收率地得到了含多官能团的CycI[3,2,2]azine衍生物。
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The results showed that the preoxidation of PPESK was a free radicals reaction,which was initiated by the decomposition of proton in aromatic ring and sulfone functional group and the removal of H_2O and SO_2.When the preoxidation temperature was above 460℃,the radical reaction was initiated by the decomposition of ketone functional group and the removal of CO_2.At last,the three-demensional cross-linking structure containing polyaromatic ether and biphenyl was formed.
研究表明,PPESK的预氧化过程是一个自由基反应过程,始终伴随着芳香环质子和砜基官能团的脱除引发的自由基交联反应,脱出H_2O与SO_2;当预氧化温度超过460℃后,随着反应的进行,由羰基官能团分解引发的自由基交联反应开始发生,脱出CO_2,并最终形成了含有大量聚芳醚和联苯结构的稳定的三维空间网状结构,进而完成PPESK由热塑性材料向热固性材料的转化。
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A brief review of preparation of three 1,1'binaphthyls with nonidentical groups in 2, 2'positions: 2amino2'hydroxy1,1'binaphthyl, 2hydroxy2'mercapto1,1'binaphthyl and 2amino2' mercapto1,1'binaphthyl was prespented, and the progress on their application in the asymmetrical synthesis was outlined.
概述了 2 ,2'位置上带有不同取代基的 1,1'联萘化合物,如 2氨基 2'羟基 1,1'联萘、2羟基 2'巯基 1,1'联萘和 2氨基 2'巯基 1,1'联萘的制备及在不对称合成中的应用研究进展。
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In the three systems, system realizes the crosslinking of PVC bases on the peroxide crosslinking mechanism, the tensile strength of crosslinked PVC has been improved somewhat, the IR spectrum of gel demonstrates that there are characteristic absorption peaks of n-alcohol that belongs to ethanol amine and benzenoid group. From the analysis of gel structure , deduces that the mechanism of crosslinking reaction: under the initiations of peroxide and high temperature, PVC yields macromolecules free radicals, at the same time , styrene"s polymerization and grafting onto PVC takes place, at last the system forms crosslinking structure through coupling between radicals; confirms that triethanol amine can absorb HC1 produced by degradation of PVC, so improves the crosslinking efficiency of peroxide, decreases the HCl"s promotion for PVC"s degradation; deduces that triethanol amine can activate the PVC macromolecules and prolong the free radicals" life-time of PVC macromolecules; the effect to the PVC macromolecule makes styrenes graft reaction easy, and thus improves the crosslinking efficiency.
三种体系中三乙醇胺/过氧化二异丙苯/苯乙烯体系基于过氧化物交联机理实现了聚氯乙烯的交联,聚氯乙烯交联后拉伸强度有一定提高,凝胶红外光谱分析证实了凝胶结构中含有乙醇胺的伯醇基团特征吸收和苯环的特征吸收,由凝胶结构分析,推断出交联反应的机理:聚氯乙烯在过氧化物和热作用下产生大分子自由基,苯乙烯在过氧化物和大分子自由基的作用下发生聚合和接枝反应,最终通过自由基之间的偶合产生交联;证实三乙醇胺可以吸收聚氯乙烯分解产生的HCl,提高了过氧化物的交联效率,消弱了HCl对聚氯乙烯降解的促进作用;推断三乙醇胺可以活化聚氯乙烯大分子并有可能使聚氯乙烯大分子自由基存在的时间得以延长,对聚氯乙烯大分子的作用使苯乙烯的接枝反应易于发生,从而提高了交联效率。
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In this paper,- and (5)-2,2'-diethynyl-1,1'-binaphthyl with highly stable chiral configurations were employed as structural templates, and a new type of helical cyclophane compounds-3 and-3 were synthesized in enantiopure form by the introduction of benzyl sulfone through Sonogashira coupling reaction, followed by the treatment of disulfone with lithium diisopropylamide.
基於2,2'-二取代的联萘衍生物在手性构型上高度稳定的特点,分别从光学活性的-和-2,2'-二乙炔基-1,1'-联萘结构模板出发,通过Sonogashira偶连反应导入苄基碸,然后用二异丙基氨基锂处理制得的联萘二碸成功地合成了一种新的螺旋环芳分子-对映异构体-3和-3。
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The chapter two was focused on the samarium diiodide promoted organic reactions and their applications in organic synthesis, firstly, a new synthesis of highly substituted cyclopentadienes from a,β-alkynone promoted by samarium diiodide was investigated and the highly substituted cyclopentadienes were prepared in moderate to good yields under mild conditions. Secondly, the Michael addition and Michael-aldol tandem reaction of diorganyl diselenides or diorganyl disulfides with α,β-alkynones mediated by samarium diiodide were studied and a series of alkenylsulfides and alkenylselenides were prepared in good yields. Then the highly regioselecfive nucleophilic addition of the allylsamarium bromide to α,β-alkynones were explored. We found that the allylsamarium bromide reacts with α,β-alkynones to afford regiospecificly 1. 2-nucleophilic addition products in good yields under mild condition. At last we studied the coupling reaction of aryl halides promoted by NiCl〓/PPh〓/Sm〓.
第二章 研究了二碘化钐、金属钐促进的有机反应:1、二碘化钐促进下α,β-炔基酮的偶联环化反应,提供了一种制备多取代环戊二烯的新方法;2、二碘化钐促进下的二硫醚、二硒醚与α,β-炔基酮的Michael加成反应,为高产率地制备多取代的烯基硫或烯基硒化合物提供了方便可靠的新方法;3、二碘化钐促进下的二硫醚、二硒醚与α,β-炔基酮和醛、酮的Michael—aldol串联反应,提供了一种一锅法高产率地制备多取代的含硫的烯丙基醇或含硒的烯丙基醇类化合物的方便可靠的原子经济性的新方法;4、烯丙基溴化钐与α,β-炔基酮的高度区域选择性的1,2-亲核加成反应;5、NiCl〓/PPh〓/Sm〓促进的卤代芳烃的偶联反应-一种从各种卤代芳烃制备联苯类化合物的有效方法。
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The solid-liquid reaction method was used for the preparation of HPLC aryl-bonded silica gel stationary phases, including 3, 5-dinitrobenzyl, quinolinyl ether and 1, 1'-di(2-naphthol) ether bonded silica gel stationary phases by using N-(β-aminoethy1)-γ-aminopropylmethyldimethoxy silane and 3-glyci-doxypropyl trimethoxylsilane as coupling reagents, respectively.
采用固液相连续反应,以N--γ-氨丙基甲基二甲氧基硅烷和γ-丙基三甲氧基硅烷为偶联剂,分别制备了二硝基苯甲酰胺基、喹啉醚基和联萘酚醚基三种芳基键合硅胶固定相。
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The compound of BNTMBP wassynthesized by the condensation reaction between 4-chloronitrobenzene (4CNB) and 4, 4'-dihydroxy-3, 3', 5, 5'-tetramethyl biphenyl in the presence of potassium carbonate in the mixture solvents of N, N-dimethylformamide and tolune.
4, 4'-二羟基-3, 3', 5, 5'-四甲基联苯、4-氯硝基苯(4CNB)和碳酸钾在N, N-二甲基甲酰胺和甲苯的混合溶剂体系中回流反应,合成得到了4, 4'-双(4-硝基苯氧基)-3, 3', 5, 5'-四甲基联苯;随后,在Pd/C-水合肼的还原体系中,被进一步还原,得到了4, 4'-双(4-氨基苯氧基)-3, 3', 5, 5'-四甲基联苯。
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In chapter four, molecular imprinting polymers against amino acid derivatives utilizing 2-VP+AM as combined functional monomer and trimethylolpropane trimethacrylate as tribasic cross-linker were prepared and result was compared with those with the same amino acid derivative as the imprinted molecules utilizing ethyleneglycol dimethacrylate as dibasic cross-linker. It was found that cross-link intensity of the molecular imprinting polymer is higher when TRIM was utilized and baseline separation for the imprinted molecule could be achieved. When TRIM was utilized as cross-linker more molecule is imprinted during the polymerization.
第四章采用2-乙烯基吡啶+丙烯酰胺复合功能单体,考察了三元交联剂三甲氧基丙烷三甲基丙烯酸酯烙印氨基酸衍生物的情况,并与二元交联剂乙二醇二甲基丙烯酸酯烙印相同氨基酸衍生物的情况进行了对比,发现三甲氧基丙烷三甲基丙烯酸酯交联剂在较小的用量下就可使分子烙印聚合物达到足够的交联度,实现烙印分子的基线分离。
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By synthesizing the hapten LBc starting from the metabolite of bifenthrin (2-methyl-3-phenylbenzyl alcohol), LBs (2-methyl[1,1-biphenyl]-3-ylmethyl 3-carboxyl-2,2-dimethylcyclopropane carboxylate and Lby (2-methyl[1,1-biphenyl]-3-ylcarboxylic acid , Three haptens were praparaed which were used in next step.
利用联苯菊酯的代谢物联苯醇合成了联苯菊酯的半抗原LBc(2-甲基-3-苯基苄基氧基羰基丙酸)、LBs(2-甲基-3-苯基苄基-3-羧基一2,2-二甲基环丙烷羧酸)和LBy(2-甲基-3-苯基苯甲酸)。
- 推荐网络例句
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As she looked at Warrington's manly face, and dark, melancholy eyes, she had settled in her mind that he must have been the victim of an unhappy attachment.
每逢看到沃林顿那刚毅的脸,那乌黑、忧郁的眼睛,她便会相信,他一定作过不幸的爱情的受害者。
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Maybe they'll disappear into a pothole.
也许他们将在壶穴里消失
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But because of its youthful corporate culture—most people are hustled out of the door in their mid-40s—it had no one to send.
但是因为该公司年轻的企业文化——大多数员工在40来岁的时候都被请出公司——一时间没有好的人选。