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Allylic co-monomers such as diallyl adipate and triallyl citrate also formed interesting co-polymers and ter-polymers with DAP.

烯丙基共同单体如烯丙基己二酸和 triallyl柠檬酸还形成了有趣的共同聚合物和相聚合物DAP。

The auxiliary can be recovered in high yield (81%) only by filtering and recrystallization. Besides, some other aldehydes have been chosen to test the enantioselectivity of N,N\'-dibenzyl tartamide, in comparison with two other allylaborates reagents developed previously by Roush and Brown, respectively. The results show that %e.e. of homoallylic alcohol is superior to that of the former, and approaches the Brown reagent.

产物经S_N2反应得瑞格列萘中间体-甲基烯丙基-2-氯苯基-叠氮甲烷(17);同时,将筛选出的新型手性配体N-苄基酒石酸二酰胺用于其他几种醛(正丁醛,异戊醛和环己醛)的不对称烯丙基化反应,并与广泛应用的Roush配体(22)和Brown配体(27)相比较,发现其立体选择性优于Roush配体,并接近Brown配体,但明显具有可回收利用的优势。

Second, using DBU as the base for enolization of propargylic esters of unsaturated acids 18e-k, we developed a tandem Ireland-Claisen rearrangement /isomerization reactions. It has been shown that the reaction sequence affords triene molecules 42a-b and 43a-b in moderated to high yields. Interestingly, with allyl hexa-3,5-dienoates 18i-j as the substrate, the rearranged products underwent further aromatization to give uniquely substituted benzyl acids 44a-b.

其次,以含有活泼质子的烯酸炔丙酯18e-k为底物,在DBU为烯醇化碱、TMSCl为硅试剂的条件下,底物18e-h发生了Ireland-Claisen重排/异构化串联反应,得到完全共轭的三烯类化合物42a-b及43a-b;而以己二烯酸炔丙基酯18i-j为底物时,重排/异构化后的产物进一步发生电环化等反应最终得到芳构化产物——取代苯甲酸类化合物44a-b。

This dissertation focused on two types of reactions, oxidative allylation of 1, 3-dicarbonyl compounds and ring-opening allylation of epoxides.

我们重点考察了两类反应:1, 3-二羰基类化合物的不对称烯丙基化反应和环氧化合物的开环烯丙基化反应。

The third part of this thesis is reactive simulating calculation In this section, some well-known auxiliaries are selected to compute in density functional theory B3LYP on Gaussian 03, from which the relationship between reaction active energies of transition states and enantiomeric excess of chiral products homoallylic alcohols isobtained based on relative reactive ratio theory. Using this relationship, calculations on the reaction of more than eight auxiliaries with four other aldehydes are carried out in AMI and MNDO, proving that N,N\'-dibenzyl tartamide has higher enantioselectivity than others in this reaction.

第三部分为计算化学部分,运用密度泛函理论B3LYP方法在Gaussian03软件上对已经报道的几种手性配体参与的醛不对称烯丙基化反应过程进行模拟计算,基于相对反应速率理论找出两种构型过渡态间活化能的差异与产物光学收率之间的关系;并以此为基础,用AM1和MNDO方法对上述合成的几种配体控制的反应过程进行量化计算,从而在理论上证实了N-苄基酒石酸二酰胺配体在醛的不对称烯丙基化反应中具有较高的立体选择性。

In a similar way, using N,N\'-dibenzyl tartamide as auxiliary,-(2-methyl)allyl-2-chloro-phenyl-methyl azide, a vital intermediate of Repaglinide, can be prepared via asymmetric allylation of o-chlorobenzaldehyde in

产物经氧化和碘加成内酯化反应得到阿伐他汀中间体(3R,5S)-3-羟基-5-碘甲基戊内酯(10);将N-苄基酒石酸二酰胺用于邻氯苯甲醛的不对称烯丙基化反应以较高光学收率得-甲基烯丙基-2-氯苯基-甲基醇

Reaction of 5'-O-p-methoxytrityl-thymidine with 1, 1'-carbonyl-diimidazole gave the 3'-O-carbonylimidazolide, which was condensed in high yield with 3'-O-protected thymidine to give a dithymidine carbonate. In the same way, we obtained the protected trithymidine dicarbonate. After deprotection, we obtained quantatively the trithymidine dicarbonate.By the same stratagy, we completed the synthesis of dithymidine sulfite.It was shown that allyl can be used as a good protection group for hydroxyl of ribose in the synthesis of oligonucleotides consisting in some unstable nucleotide analogues.

我们在第一部分工作的基础上,以烯丙基作为3'-OH的保护基合成了保护的三胸苷碳酸酯以及二胸苷亚硫酸酯,用我们所得的脱保护条件进行了脱保护研究,得到了三胸苷碳酸酯以及二胸苷亚硫酸酯,并研究了它们合成中的一些化学问题,结果表明:烯丙基能很好地运用于这两类寡核苷酸类似物的合成中,其脱保护条件为中性,不会影响碳酸酯键及亚硫酸酯键。

It is found that the stereochemistry of the reactions of telluronium allylide,crotonylide and trimethylsilyallylide with α,β-unsaturated esters and amides can be tuned by thechoice of reaction conditions.

利用反应条件的变化首次实现了烯丙基、巴豆基、含硅烯丙基碲叶立德与α,β-不饱和酯、酰胺进行环丙烷反应的立体化学调控,能高立体选择性地、高效率地合成两种不同几何异构体中的一个。

The algicidal performances of monomer dimethyldiallylammonium chloride and a commercial algicide dodecyldimethylbenzylammonium chloride( 1227 ) were contrasted with that of PDM.

对两种营养化的模拟水体,通过灭藻实验,研究了聚二甲基二烯丙基氯化铵系列样品的静态灭藻性能,考察了加药量、作用时间、特征黏度等因素对灭藻性能的影响规律,并与聚合物单体二甲基二烯丙基氯化铵及市售灭藻剂十二烷基二甲基苄基氯化铵(1227)的灭藻性能进行了对比。

Then, it was condensed with-valine methyl ester to form a chiral imine, which was reacted with allyl zinc bromide in the presence of CeCl3·7H2O to afford the corresponding chiral homoallylic amine with high optical activity.

-N-Boc-3-苯基-2-氨基丙醛与-缬氨基酸甲酯缩合生成手性亚胺,在七水合三氯化铈(CeC13·7H2O)催化以及底物的手性诱导作用下,该手性亚胺与烯丙基溴化锌经不对称加成反应合成了高光活性的单烯丙基化手性胺。

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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。