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In the first part, we studied the possibility of allyl as the protection group of the hydroxyl in nucleosides.

烯丙基作为糖化学中的一种常用保护基在核酸化学中有一定的应用,曾有人将它作为磷酸酯键及碱基环上羰基的保护基,但作为核苷糖环羟基的保护基还未有研究。

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。

Such a method can replace traditional reaction with phosgene as the carbonylation reagent, involving the toxic reagent and drastic reaction conditions, the new herein studied method is environmentally benignancy and has atom economical selectivity.

它可代替以往的利用光气来给化合物引进一个羰基的方法,具有原子经济反应的高选择性和对环境的友好性,从而越来越受到人们的关注,已成为C〓化学中羰基合成领域的一个重要的研究热点。

In our research on study chemical reaction of active methylene compounds and brom-acetophenone. Because of brom-acetophenone is compound that contain carbonyl and halogen ,which will take place electrophilic substitution and nucleophilic addition. When active methylene compounds are ethyl acetoacetate and β-diketone, controlling reaction condition, we have found that mono-substitution's production and di-substitution's. production is isolated; active methylene compounds are acetoacetanilide and acetoacetanilide derivate, pyrrolidin-2-one derivants were obtained by substitution and close-ring reaction .but there is no report about it.

本文是让活泼亚甲基类化合物与溴代苯乙酮发生化学反应,由于溴代苯乙酮是含有羰基的卤代烃结构,它可以发生亲电取代和亲核加成反应,当活泼亚甲基类化合物为乙酰乙酸乙酯和β-二酮时,控制反应条件可以发生单取代和双取代两种产物;当活泼亚甲基类化合物为乙酰乙酰芳胺类化合物来反应时,溴代苯乙酮中的羰基与氨基会发生分子内的关环反应生成吡咯烷-2-酮衍生物,这在以前的研究中是没有发现的。

Other methyl nucleophiles includingMeMgBr, MeCeCl2, MeTiCl3, Me3Al, Me3ZnMgCl, MeMnClwere tried, but in all these cases no detectable amount of exo-C8-methylated product was obtained. Although protecting C3-carbonyl as 1,3-dioxolanes could be achieved, the serious enolization of C8-carbonyl was still problematic. Converting C9-furan ring to α,β-butenolide did depress the enolization, but desired C8-methylation was completely replaced by migration of the double bond of the butenolide.

在本论文的早期阶段,主要着眼于解决二环[3.2.1]-C8-羰基加成甲基所遇到的C9-呋喃环差向异构化和C3与C8两个羰基之间化学选择性的问题:通过引入不同金属降低甲基试剂的碱性并没有取得甲基化的成功;通过不同的方法将C3-羰基掩蔽,但是C8-羰基的烯醇化依然无法抑制;虽然通过将呋喃环转化为α,β-不饱和-γ-丁内酯可以抑制烯醇化,但内酯环上的双键迁移又成了新的竞争反应。

Two isoxazole intermediates containing 1,2,3triazolyl and carbonyl ,which can also be used as intermediates for synthesis of new heterocyclic compounds,have been synthesized.

以2-苯基-1,2,3-三唑-4-甲醛为原料,合成2种在异噁唑环上同时含有1,2,3-三唑基和羰基的新型化合物,它们可作为合成其他杂环化合物的中间体,其分子结构经IR,1HMR,MS谱确证

This section includes the nonindustrial preparation, purication, and reactions of inoganic substances:elements; inorganic acids, bases, and salts; synthetic minerals; inclusion compounds;charge-transfer complexes; coordination compounds containing inoganic and organic ligands;nonmetal and metalloid compounds; and carbon-containing compounds such as the carbon oxides, metal carbonyls, carbonates and transition metal carbonxylates.

这一章节涵盖了无机物的非工业制备、提纯、及反应:元素;无机酸、基团和盐类;合成矿物质;包藏复合物;转移电荷复合物;包含了无机和有机配合基的配位化合物;非金属与非金属化合物;以及含碳化合物,如碳氧化物、金属羰基、碳酸盐和含有羰基的过渡金属等。

But under the same conditions, the reactions of the complex (41) with organic lithium reagents give a kind of novel complexes in which the nucleophile is added to the a-carbon of the phthalazine ring.

然而含有桥羰基的2,3-二氮杂萘配位的羰基双铁络合物4l在相同的条件下与芳基锂试剂反应时,芳基锂却是亲核加成在氮杂环的α位羰上,生成一类结构独特的双氮双铁羰基络合物。

It was found that PCBA-BPy and PCCA-BPy exhibited both smectic and nematic phase while all of their predecessors showed no smectic phase.

结果表明,这两个氢键复合物都具有由于分子间氢键作用而导致的近晶相,但它们中存在的氢键作用却不相同,在PCBA-BPy中,温度变化时,发生氢键结合的羰基的吸收峰的位置仅在发生晶型转变时有突变,而在PC-CA-BPy中,温度变化时,其羰基的吸收峰的位置则基本不发生突变。

After experiments, we got some results as the following:1.Induced by semi-conductor laser, solid DNA changes as below: 1the deoxyribose-phosphate backbone vibrations in DNA decreasing, these bands are at 884~890cm~(-1),1112cm~(-1) and 1168cm~(-1). 2 deoxyribose and C-O stretch vibration in d increasing, there are new bands occurring at 1436cm~(-1) and 1072cm~(-1), the intensities of these bands at 1466cm~(-1) and 1030cm~(-1) increase.

通过实验研究,得到如下一些结论: 1、固体DNA经半导体激光器照射后,可以导致以下变化:(1)DNA中脱氧核糖磷酸主链振动减弱,包括在884~890cm~(-1)、1112cm~(-1)和1168cm~(-1)处的谱带;(2)脱氧核糖以及d中CO的伸缩振动增强,在1436cm~(-1)和1072cm~(-1)处出现了新的谱带,在1466cm~(-1)和1030cm~(-1)处的谱带强度增强;(3)各碱基的振动频率和相对强度都发生了很大的变化,碱基中羰基的伸缩振动显著增强,在1650cm~(-1)和1670cm~(-1)处出现了新的谱带,在1710cm~(-1)处的谱带强度显著增强。

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