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The reaction of α-hydroxyketone with Michael acceptor nitroalkene.was studied. After many experiments, we then found that in the presence of Zn2 and cinchonine, the α-hydroxyketone could successfully react with nitroalkene. Under our optimized condition, we gained the 95% yield of product with the ratio of syn : anti of 3:1 and 72% ee value for syn-product.

有机碱作用下α-羟基酮对硝基烯烃的加成反应研究研究了α-羟基酮类化合物与Michael受体硝基烯烃类化合物的反应,通过分析和实验发现在Zn2和辛可宁的作用下α-羟基苯乙酮能够与硝基烯烃化合物顺利反应,在优化的条件下以95%产率和3:1的Dr主要得到顺式产物,其中顺式产物的ee值最高为72%。

In chapter three, molecular imprinting chiral stationary phases against amino acid derivatives utilizing 2-vinylpyridine+acrylamide (2-VP+AM) as combined functional monomers were prepared. Comparing combined functional monomer 2-VP+AM with AM and methacrylic acid+2-VP, the former, 2-VP+AM showed higher imprinting ability. Explanation was given according to the compatibleness between the functional monomer and the imprinted molecule.

第三章系统考察了复合功能单体2-乙烯基吡啶+丙烯酰胺制备氨基酸衍生物分子烙印手性固定相的情况,发现复合功能单体2-乙烯基吡啶+丙烯酰胺烙印体系与丙烯酰胺及复合功能单体2-乙烯基吡啶+甲基丙烯酸烙印体系相比,对氨基酸衍生物表现出更好的烙印能力,验证了功能单体与烙印分子之间存在着匹配性的观点。

In chapter 4 an abnormal reaction that the nitro group of 1-aryl-2-nitroethenescan be easily replaced by the organic moity of FG-RZnI using Ni〓 and tertiaryamine as catalyst was first given. The experimental results show that in the presenceof catalytic amount of Ni〓 and tertiary amines, the reaction of FG-RZnI andl-aryl-2-nitroethenes give the substitution products l-aryl-l-alkene, instead ofMichael addition products.

通过实验发现,在催化量的Ni〓及叔胺催化下, l-硝基-2-芳基乙烯与烷基碘化锌并不进行Michael加成反应,而是发生1-硝基-2-芳基乙烯中硝基被取代的反应,生成了高产率的1-芳基-l-烯烃,由于此反应的原料易得、反应条件温和、产物的产率高,因而是合成l-芳基-1-烯烃的有效方法。

Two special structural features of the sulfonium salt were proved to stabilize its corresponding ylide and depress the 2,3-sigma rearrangement. One is that there is a trimethylsilyl in the end of the allylic double band. This silicon atom can stabilize a α-carbon anion and the corresponding ylide. Another is that there is hydroxy group in the beta-position of sulfonium atom. The oxygen of this hydroxy group may stabilize the sulfonium cation.

为了稳定生成的烯丙基硫叶立德,并抑制它的2, 3-sigma 重排反应,在硫叶立德结构上做了两方面的考虑:一是在烯丙基双键的未端引入硅基,利用硅原子对 a -碳负离子的稳定作用来稳定烯丙基硫叶立德;二是在硫原子的 b -位引入羟基,利用羟基氧对硫正离子的作用来稳定硫叶立德。

Chiral homoallylic alcohol was prepared in this paper from asymmetric allylation of aldehyde with enantiomerically pure allylboronate tartramides such as chiral N,N'-diphenyl tartramide and N,N'-di...

本文以手性烯硼酸丙基酒石酸酰胺酯(如烯丙基硼酸-N,N'-二苯基酒石酸酰胺酯)为辅基,进行醛的不对称烯丙基化反应研究。

Master the Keto-Enol tautomerism; reactions of enols:α-H substitution reactions;α-halogenation of aldehydes and ketones;α-bromination of carboxylic acids; acidity ofα-H atoms: enolate ion formation; reactivity of enolate ions; alkylation of enolate ions; mechanism of carbonyl condensation reactions;condensations of aldehydes and ketones: the Aldol reaction; dehydration of Aldol products; the Claisen condensation reaction; the Michael addition.

熟练掌握酮式-烯醇式互变异构;烯醇的反应:α-H的活性;醛酮的α卤代反应;羧酸的α-溴代反应;α-H的酸性:烯醇负离子的形成;烯醇负离子的反应;烯醇负离子的烃基化;羰基化合物的缩合反应机理;醛酮的缩合反应-Aldol缩合;Aldol缩合产物的脱水反应; Cleisen 酯缩合反应;麦克尔加成反应。

In part one, the reactions of some active fluorine-containing compounds such as 2, 2-dihydropolyfluoroalkanoic acids and ethyl 2-hydropolyfluoroalkenoates were studied and various fluorine-containing heterocyclic compounds were synthesized. Using 2, 2-dihydropolyfluoroalkanoic acids as the starting material, 4-fluoroalkyl quinolin-2-ols, 2- [ -1-hydropolyfluoro-1-alkenyl] -4H-3, 1-benzoxazin-4-ones, 1-aryl -4, 9-dihydro-3-fluoro-alkyl-1H-pyrazo [3, 4-b] quinolin-4-ones, 5-fluoroalkyl-12H-quin olino [2, 1-b] quinazolin-12-ones, 4-fluoroalkyl-1, 3-dihydro-1, 5-benzodiazepin-2-ones and 4-fluoroalkyl-2H-pyrido [1, 2-a] pyrimidin-2-ones were synthesized through its condensation reaction with anilines, anthranilic acid, N'-aryl-o-aminobenzamides, o-nitro aniline, o-amino pyridine and their derivatives and the subsequent transformations. 5-Fluoroalkyl isoxazolidines, 3-fluoro-3-fluoroalkylisoxazolidino [4, 3-c] quinolin-4-ones, 3-fluoroalkylisoxazolino [4, 3-c] quinolin-4-ones and 2-aryl-3per fluoroacylindoles were synthesized by inter-and intramolecular 1, 3-dipolar cycloaddition of fluorine-containing olefins and nitrones.

第二部分,我们研究了α,α-二氟苄基卤类化合物的亚磺化脱卤反应、产物的转化及全氟烷基亚磺酸盐与芳环化合物的全氟烷基化反应,发现全氟苄基碘或溴及α,α一二氟苄基溴在保险粉等亚磺化脱卤试剂引发下可生成相应的亚磺酸盐;全氟苄基亚磺酸盐与氯气或溴反应可生成全氟苄基磺酰氯或磺酰溴;在烯烃存在下,全氟苄基碘则与烯烃发生加成反应,生成相应的1:1加成产物;在三价醋酸锰的作用下,部分芳香化合物如茴香醚,二甲氧基苯,吡啶,喹啉等可以和过量的全氟烷基亚磺酸盐发生双全氟烷基化反应,反应表现出一定的区域选择性,产率良好。

In this paper,firstly a series of acryloxyl derivatives were synthesized from the dehydrogenated abietic acid,a main composition of disproportionated rosin, through acyl chloridation and esterification.The derivatives included the (β-acryloxyl ethyl) esters of dehydrogenated abietie acid,(β-methacryloxyl ethyl) esters of dehydrogenated abietic acid and (β-methacryloxyl propyl)esters of dehydrogenated abietic acid.

论文首先以歧化松香中的主要成分脱氢枞酸为模型化合物,采用酰氯化、酯化手段合成了它的一系列丙烯酰氧基衍生物,包括脱氢枞酸酯、脱氢枞酸(β-甲基丙烯酰氧基乙基)酯和脱氢枞酸(β-甲基丙烯酰氧基丙基)酯。

SM6 and SM7 of uncrystal were analyzed through GC-MS, the results showedthat SM6 main contained unsaturated fatty aldehyde with fragrance, i.e.-2,4-decadienal(58%), tetradecanoic acid (55.78%), 2-decenal(50%), Phthalic acid isobutylundecyl ester(47%), 2, 4-Decadienal(41%), 2-Undecenal (31%), 2-Methyl-Z,Z-3, 13-octadecadi-enol(18.84%), and SM7 contained saturation alkanes, i.e. 1, 2-Benzenedicarboxylic acid, butyl cyclohexyl ester(23.90%), Triacontane(22.63%),Nonacosane(21.04%), Heptadecane(18.84%), Octacosane(13.58%). Toxicological experiments were done to insure the pigment safety.

并对紫红丝膜菌色素非晶体部分的黄色油状物SM6和紫色粉末物SM7作了GC-MS分析,结果显示SM6中主要为具有香气成分的不饱和脂肪醛,其中含量较高的依次为:-2,4-癸二烯醛(58%)、十四烷酸(55.78%)、2-癸烯醛(50%)、邻苯二甲酸异丁基十一烷酯(47%)、2,4-癸二烯(41%)、2-十一碳烯醛(31%)、2-甲基-Z,Z-3,13-十八碳二烯酸(18.45%)等;SM7中主要为饱和直链烷烃,其中含量较高的依次为:1,2-苯二羧酸丁基环己酯(23.90%)、三十烷(22.63%)、二十九烷(21.04%)、十七烷(18.84%)、二十八烷(13.58%)。

Two new active esters of acrylic acids monomers, N-p-acryloxybenzoyloxy succini-mide and N-p-methacryloxybenzoyloxy succinimide have been synthesized and polymerized.ABOSu and MBOSu were prepared by coupling of p-acryloxybenzoic acid or p-methacryloxybenzoie acid with N-hydroxy succinimide in the presence of dicyclohexylcarbodimide.

新的丙烯酸活性酯,N-(对甲基丙烯酰氧苯甲酰氧基)丁二酰亚胺及N-丁二酰亚胺单体分别由对甲基丙烯酰氧基苯甲酸、对丙烯酰氧基苯甲酸与N-羟基丁二酰亚胺在环已基羰二亚胺存在下经偶联反应合成。

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推荐网络例句

We have no common name for a mime of Sophron or Xenarchus and a Socratic Conversation; and we should still be without one even if the imitation in the two instances were in trimeters or elegiacs or some other kind of verse--though it is the way with people to tack on 'poet' to the name of a metre, and talk of elegiac-poets and epic-poets, thinking that they call them poets not by reason of the imitative nature of their work, but indiscriminately by reason of the metre they write in.

索夫农 、森那库斯和苏格拉底式的对话采用的模仿没有一个公共的名称;三音步诗、挽歌体或其他类型的诗的模仿也没有——人们把&诗人&这一名词和格律名称结合到一起,称之为挽歌体诗人或者史诗诗人,他们被称为诗人,似乎只是因为遵守格律写作,而非他们作品的模仿本质。

The relationship between communicative competence and grammar teaching should be that of the ends and the means.

交际能力和语法的关系应该是目标与途径的关系。

This is not paper type of business,it's people business,with such huge money involved.

这不是纸上谈兵式的交易,这是人与人的业务,而且涉及金额巨大。