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The alkoxyl group at 2-position is affected by the steric repulsion due to the two methyl groups at 1, 3-position, which causes the oxygen atom of alkoxyl group to deviate from the aromatic ring plane, hence, the conjugation effect of the oxygen atom with aromatic ring decreases

对于IV〓、IV〓,其1,3-位两个甲基对2-位烷氧基产生空间排斥作用,使2-烷氧基氧原子偏离环平面,烷氧基对环的助色作用受到削弱。

The invention provides a method for homopolymerizing conjugated dialkene or co-polymerizing conjugated dialkene and monovinyl aromatic hydrocarbon. The method comprises the following steps: the conjugated dialkene is homopolymerized or the conjugated dialkene and the monvinyl aromatic hydrocarbon are co-polymerized randomly. The method is characterized in that at least one alkali metal alkoxide compound expressed by the formula is used as a structure regulator; in the formula, R is linear chain or branched chain alkylidene radical having 1 to 10 carbon atoms; M is alkali metal selected from Li, Na, K, Rb and Cs.

本发明提供了一种使共轭二烯烃均聚或者使共轭二烯烃与单乙烯基烃共聚的方法,包括在阴离子聚合条件下使共轭二烯烃进行均聚或者使共轭二烯烃与单乙烯基烃进行无规共聚,其特征在于采用至少一种式所示的碱金属醇盐化合物作为结构调节剂,其中R为具有1-10碳原子的直链或支链亚烷基;以及M为选自Li、Na、K、Rb和Cs的碱金属。

The invention concerns a process for preparing heterocyclic carbenes of general formula in which R1, R2, R3 and R4 are identical or different and mean saturated or unsaturated, straight-chain, branched or cyclic, unsubstituted or substituted C1-C10 alkyl, C2-C5 alkylidene, C2-C5 alkylidine, C7-C19 aralkyl or C6-C14 alkyl groups, R3 and R4 can also stand for hydrogen or form jointly anellated, substituted or unsubstituted groups with between 3 and 7 carbon atoms and X stands for carbon or nitrogen, R3 being dropped if X is nitrogen.

本发明涉及一种制备通式Ⅰ的杂环碳烯的方法,其中在通式Ⅰ中,R1、R2、R3和R4是相同的或不同的,并且是饱和的或不饱和的,直链、支链或环状的,未取代或取代的C1-C10-烷基、C2-C5-亚烷基、C2-C5-次烷基、C7-C19-烷基或C6-C14-基基团,R3和R4可以是氢或它们一起形成具有3-7个碳原子的稠合的、取代或未取代的基团,X是碳或氮,并且当X是氮时,不存在R3。

The resulting epoxy resin cured with phosphorus-containing aralkyl cyanate ester exhibited better the glass transition temperature and modulus of elasticity than epoxy resin cured with phosphorus-containing aralkyl novolac resin.

实验结果显示,含磷烷基氰酸酯之环氧树脂硬化物,由於形成坚硬的Oxazolidone结构,使得其玻璃转移温度与弹性储存模数较含磷烷基酚醛树脂之环氧树脂硬化物为高。

In the presence of ethanol- HCl solution, arylamine-HCl and w=37% aqueous formaldehyde solution or the condensation product of arylamine and formaldehyde are directly reacted with ethyl 3-oxo-2-phenylmethylenebutyrate to form l-aryl-2-phenyl-3-carbethoxy-4-piperidone.

2-苯亚甲基-3-丁酮酸乙酯与香胺和w=37%甲醛水溶液或胺和甲醛的缩合物在氯化氢-无水乙醇存在下可直接发生的Mannich反应,得到1-对位取代基-2-苯基-3-羰乙氧基-哌啶-4-酮。

Making use of this reaction, thirteen methyl 2-arylamino-2-deoxy 3-keto glucopyranosides (5~17) with different substituted arylamino groups and two

选择不同类型的胺利用该反应合成了一系列共十三种2-脱氧2-胺基3-位氧化α-甲基D-葡萄糖苷(5~17),该类化合物为重要的手性合成子。

The Knoevenagel condensation reactions between aromatic and α,β-unsaturated aromatic aldehydes with barbituric acid can effectively be performed in ionic liquid without additional acid or base catalyst, it is a simple efficient method for the synthesis of benzylidene barbituric acids, which have been widely used in pharmaceutical chemistry as well as in organic synthesis.

醛、α,β-不饱和醛和巴比妥酸间的Knoevenagel缩合反应能在离子液体中没有酸碱催化剂的条件下顺利进行,是合成在药物化学和有机合成中有广泛用途的苯亚甲基巴比妥酸类化合物的简单有效的方法。

In this thesis, investigations focused on heteropoly acids-catalyzed C-C and C-N bond formation reactions and the synthesis of xanthenediones and acridinediones under thermal conditions are described.1.12-Phosphotungstic acid has been used as an efficient,eco-friendly,and air- and moisture-stable catalyst to promote the direct dehydrative substitution of the hydroxy group of benzylic and allylic alcohols with variousβ-dicarbonyl compounds.

本篇论文主要描述了杂多酸催化下的C-C和C-N键的生成,以及无溶剂直接加热下合成十氢氧杂蒽二酮和9-基十氢吖啶二酮。主要内容如下:1。在磷钨酸催化下,1,3-二羰基化合物与醇能够顺利偶合,脱除一分子的水,生成烷基化的1,3-二羰基化合物。反应在甲苯中进行时,二基甲醇能与各类1,3-二羰基化合物反应,成率很高;但对于1-苯乙醇,只能得到很低的产率。

Poly with sulfonic acid groups were readily synthesized with biphenol and 1,3-bis(4-fluorobenzoyl)benzene in the presence of excess potassium carbonate followed by sulfonation with chlorosulfonic acid.

以二氯二苯甲烷和2,6-二甲基苯酚为原料合成了含有阻碍基团的双酚单体,用此双酚单体和1,3-二(4-氟苯甲酰基苯)在无水碳酸钾存在的条件下反应制得聚醚酮,然后用氯磺酸磺化,控制反应条件,使磺酸基团恰好进入苯环对位,制得新型结构的磺化聚醚酮。

Result showed that tetrasubstituted calix [4] arenes in lower rim were stronger complex abilities than bisubstituted calix [4] arene with transition metal, heavy metal and rare earth ions. But when introducing the aminephenolicalcohols in the 1, 3-bisubstituted calix [4] arenes, the complex abilities were improved.

结果表明:在Lower rim上四取代的杯[4]烃配体比1,3-二取代的杯[4]烃配体对过渡金属离子,重金属离子及稀土离子有更好的配位能力,但当1,3-二取代的取代基上引入醇胺链型配体时,对金属离子也有很好的配位能力。

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But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊!不用提了。提到肉,真是糟透了。

Tristan, I have nowhere to send this letter and no reason to believe you wish to receive it.

Tristan ,我不知道把这信寄到哪里,也不知道你是否想收到它。