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In chapter three, the activating agents of ytterbium have been examined. Barbier-type reaction promoted by ytterbium metal was examined. The experimental results shown that the yield of Barbier reaction of imines with allylic bromide promoted by ytterbium is higher than that of aldehydes and ketones with allylic bromide under the same reaction conditions. In this chapter, the reductive cleavage of Se-Se and S-S bond induced by ytterbium metal was also studied.

首先研究了金属镱的活化剂以及活化方法,接着考察了金属镱促进的Barbier反应及其在合成高烯丙基胺和高烯丙基醇中的应用,以及影响该反应的主要因素;究了金属镱促进的二硫醚和二硒醚的S—S键和Se—Se键的还原断裂,继而与氯代烃,胺基甲酰氯反应生成相应的硫醚,硒醚,胺基甲酸硫代酯和硒代酯。

In the present study, Hartree-Fock and Density Functional Theory with different basis sets were employed to calculate the structural and thermodynamic parameters of 66 thiophenyl, phenyl sulfoxide and phenylsulfonyl cycloalkane carboxylates. With the statistic software SPSS11.5 for windows and GQSARF2.0, the QSAR models relating physicochemical properties of these compounds to their structural and thermodynamic parameters were successfully obtained, using multiple stepwise regression method. The physicochemical properties observed in this work include octanol/water partition coefficient, chromatographic capacity index, toxicity (EC50 and LC50), and solubility etc.

本文采用从头算方法中的Hartree-Fock 方法、密度泛函理论方法(Density functional theory,简称DFT)中的不同基组,计算了苯硫基、苯亚砜基和苯砜基含硫芳香羧酸酯三类共66 个化合物的结构参数和热力学参数,利用SPSS11.5 for windows 统计软件和GQSARF2.0 软件,采用多元逐步回归法拟合得到与溶质-溶剂相互作用有关的物理化学性质与结构参数和热力学参数之间的QSAR 方程,这些物理化学性质包括辛醇/水分配系数、色谱容量因子、毒性(EC50和LC50)、溶解度等。

These methanols were treated with BF3 in CH2Cl2 to generate the diferrocenylmethyl carbocations. Without separation from the reaction mixture, the ions were treated with some amines RNH2 [R=C2H5, n-C3H7, n-C4H9, HOCH2CH2, HOCH(CH3)CH2, HOCH2CH(C2H5)] to afford the ferrocenylamines in high yields. The present methodology for preparing α-ferrocenylamines from α-ferrocenyl alcohols enjoys such advantages as simple procedure and inexpensive starting materials.

它们对酸的敏感性很高,与BF3在二氯甲烷中作用可形成稳定的二茂铁基甲基碳正离子,无需从溶液中分离出来,便可与胺RNH2[R=C2H5,n-C3H7,n-C4H9,HOCH2CH2,HOCH(CH3)CH2,HOCH2CH(C2H5)]作用得到产率颇高的二茂铁基胺,这种由α-二茂铁基醇制备α-二茂铁基胺的方法具有简单、快速和原料廉价的特点。

A selective and mild PS-DIB/ionic-liquid immobilized 2, 2, 6, 6-tetramethyl-piperidin-4-ol-N-oxyl catalytic oxidation procedure of alcohols to the corresponding aldehydes and ketones in ionic liquid BF4 at room temperature was developed. The oxidant PS-DIB was prepared via the iodation and acetylation of polystyrene resin. For the preparation of the ionic-liquid immobilized TeMPO catalyst, 4-(2, 2, 6, 6-Tetramethyl-1-oxyl-4-piperidoxyl)butyl bromide was first synthesized from TeMPO and 1, 4-dibromobutane.

将聚苯乙烯树脂先碘化再乙酰基化,制得了负载型二乙酰氧碘苯作为氧化剂。2, 2, 6, 6-四甲基-N-氧自由基哌啶醇与1, 4-二溴丁烷反应生成4-溴丁氧基-2, 2, 6, 6-四甲基-哌啶-1-氧化物,再与N-甲基咪唑发生季铵化反应,生成的溴化季铵盐与四氟硼酸钠进行离子交换制得氟硼酸型2, 2, 6, 6-四甲基-N-氧自由基哌啶负载离子液体。

A selective and mild PS-DIB/ionic-liquid immobilized TEMPO catalytic oxidation procedure of alcohols to the corresponding aldehydes and ketones in ionic liquid BF4 at room temperature was developed. The oxidant PS-DIB was prepared via Iodation and acetylation of polystyrene resin. For the preparation of the ionic-liquid immobilized TEMPO catalyst, 4-(2,2,6,6-Tetramethyl-1-oxyl-4-piperidoxyl)butyl bromide was first synthesized from 2,2,6,6-tetramethyl-piperidin-4-ol-N-oxyl and 1,4-dibromobutane.

将聚苯乙烯树脂先碘化再乙酰基化,制得了负载型二乙酰氧碘苯(diacetoxyiodo polystyrene,PS-DIB)作为氧化剂。2,2,6,6-四甲基-N-氧自由基哌啶醇(2,2,6,6-tetramethyl-piperidin-4-ol-N-oxyl,TEMPO)与1,4-二溴丁烷反应生成4-溴丁氧基-2,2,6,6-四甲基-哌啶-1-氧化物,再与N-甲基咪唑发生季铵化反应,生成的溴化季铵盐与四氟硼酸钠进行离子交换制得氟硼酸型2,2,6,6-四甲基-N-氧自由基哌啶负载离子液体TEMPO-IL。

Their structures were identified by chemical and spectral analysis. RESULTS Five compounds were isolated and identified as stigmasterol 3-O-β-D-glucopyranoside, 20β-hydroxy-ecdysone,β-L-thymidine, pennogenin 3-O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside and pennogenin 3-O-α-L-rhamnopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→4)-[α-L-rhamnopyranosyl-(1→2)-]-β-D-glucopyranoiside.

结果 分离并鉴定了5个化合物,分别是Δ5,22-豆甾醇3-O-β-D-葡萄吡喃糖苷,20β-羟基蜕皮激素,β-L-脱氧胸腺嘧啶苷,偏诺皂苷元3-O-α-L-鼠李吡喃糖基-(1→2)-β-D-葡萄吡喃糖苷和偏诺皂苷元3-O-α-L-鼠李吡喃糖基-(1→4)-α-L-鼠李吡喃糖基-(1→4)-[α-L-鼠李吡喃糖基-(1→2)-]-β-D-葡萄吡喃糖苷。

The main varieties are: Blending alkyd paint, alkyd varnish, alkyd enamel, paint phenolic resin, amino paint, distempers Mastics, high-grade polyurethane paint, acrylic paint, metallic paint, car paint, bitumen paint, polyester wood at the end of paint and finish, the middle-grade interior and exterior wall latex paint.

主要品种有:醇酸调合漆、醇酸清漆、醇酸磁漆、酚醛树脂漆、氨基漆、硝基漆、高档聚氨酯漆、丙烯酸漆、金属漆、汽车漆、沥青漆、木器聚酯底漆及面漆、中高档内外墙乳胶漆。

In the existing process of PVB, it has disadvantages of unsteady aldehyde groupdistribution, low content of aldehyde acetal group .

本文针对聚乙烯醇缩丁醛传统生产工艺生产的PVB存在缩醛基分布不均,缩醛度低等缺陷,系统地研究了分阶段醇解一缩合的均相工艺,二甲基亚砜的均相工艺以及极性匹配的醇法均相工艺。

The alkaline earth calcium presents higher reaction activity comparing to magnesium.

碱土金属钙醇盐为烷氧基提供者制备稀土醇盐其反应活性要高于金属镁醇盐。

For the asymmetric reduction ofα-hydroxyacetophenone and ethyl 4-chloro acetoacetate,-1-phenyl-1,2-ethanediol and-ethyl 4-chloro-3-hydroxybutanoate were produced by the purified enzyme, with the 99% and 94.3% e.e. value respectively.

在纯酶水平验证了近平滑假丝酵母(Candida parapsilosis CCTCCM203011)对外消旋苯基乙二醇的拆分机理,整个去消旋过程是由-苯基乙二醇次级醇脱氢酶和羰基还原酶共同催化完成的。

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On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面,更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值,分为几个相等的区间作为横轴,并将各区间内所测定值依所出现的次数累积而成的面积,用柱子排起来的图形,也叫做柱状图。

You rap, you know we are not so good at rapping, huh?

你唱吧,你也知道我们并不那么擅长说唱,对吧?