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We show that Jordan multiplicative bijective maps on prime operator algebrasmust be additive. As its application, we show that every Jordan * multiplicative bijec-tive map on every factor C~* algebra is a C~* isomorphism or a conjugate C~* isomorphism,in the special case of B, it must be a *-isomorphism or a conjugate *-isomorphism.We also prove the additivity of Jordan multiplicative bijective maps on nest algebras.

证明了素算子代数上Jordan可乘双射的可加性,利用这一结论刻画了因子C~*代数上的Jordan*可乘双射,我们的结果表明这样的映射一定是C~*同构或共轭C~*同构;证明了套代数上的Jordan可乘双射的可加性。

Generally speaking, the reaction types involvingα-oxoketene--acetals mainly include the regioselective addition-aromatization with organometallic reagents, conjugate addition-cyclization with nitrogen nucleophilicspecies, nucleophilic reactions ofα-carbon, acting as odorless dithiol equivalentsin thioacetalization, Michael additions and [5+1] annulation, as well as the synthetic applications based on the above reactions.

一般来说,基于α-羰基二硫缩烯酮化学的反应主要为:与金属有机试剂的选择性加成反应,与氮亲核体的共轭加成反应,α-碳原子的亲核性及相关反应,烷硫基作为硫醇的替代试剂的应用,α-羰基二硫缩烯酮在碳环、杂环化合物合成中的应用等。

Furthermore, the selective reductions of 2,2'-dinitrobiphenyl have been detailedstudied in the synthesis of achiral biphenyl backbones.

运用不对称活化的策略,成功地在Cu催化Et_2Zn对链烯酮的1,4-共轭加成反应中获得了高对映体选择性的加成产物。

Carbon bisulfide was the main poison in the hydrogenation reaction of conjugated double bond of styrene and the negative effect increased with the increase of carbon bisulfide content; the negative effect decreased with the increase of reaction temperature.

二硫化碳是苯乙烯中共轭烯烃加氢快速失活的主要硫化物。随着二硫化碳含量的增加,苯乙烯中共轭烯烃加氢活性下降程度增大;随温度升高,其加氢活性下降程度减小。

Conjugate addition; indole; isatin; Gringard regeants; asymmetric addition

共轭加成;吲哚;靛红;格氏试剂;不对称加成

The structure and stability of all possible isomers of C50X(X=SiH2, PH, S) were investigated by ab initio HF/3-21G calculations. The calculation results indicate that the preferred position for cycloaddition of SiH2, PH, and S on C50 is consistent, i.e. on the C3-C4 and C4-C4 sites of C50, and the resultant most stable cycloaddition isomers are [5,6]-closed and [5,5]-closed structures. The main driving force governing the stability of the C50X(X=SiH2, PH, S) isomers is the strain, or the conjugative effect, or the combination of strain and conjugative effect, depending on the addition positions and the types of the attacked C-C bonds.

用从头算HF/3-21G方法研究了C50的环加成衍生物C50X(X=SiH2, PH, S)所有可能的异构体的结构与稳定性,计算结果表明,SiH2基团、PH基团与S原子在C50上环加成的优先加成位置相同,都为C3-C4类键和C4-C4类键,并且相应形成[5,6]-闭环和[5,5]-闭环结构的最稳定异构体;决定C50X(X=SiH2,PH,S)各异构体稳定性的主要因素,因加成位置以及发生加成反应的C-C键的单双键类型的不同,可能是张力、共轭效应或者二者的共同作用。

When equimolecular ratio of the reactants was used, the addition products were 1-phenyl-2-phenylthiopropene-1and 1-phenyl-2-phenylthiobutene-1, respectively.

这加成反应是按自由基机理进行,苯硫基联结在与烷基相邻的碳原子表明中间生成的自由基之稳定性是加成方向的决定因素,因为苯基的共轭效应比烷基为强。

The dissertation mainly consists of two parts:1. The Reaction Chemistry of Alkynes under Palladium Catalysis Part 1 studies the reaction α,β-unsaturated carbonyl compounds with alkenylpalladium intermediate generated by nucleopalladation, and discovered 1 the Pd-catalyzed tandem addition reaction of halides, alkynes and α,β-unsaturated carbonyls,2 the four-component tandem addition reaction of halides, alkynes and α,β-unsaturated carbonyls, 3 the tandem intramolecular oxypalladation-conjugate additionreaction of alkynoic acids with α,β-enals. These new reactions provide notonly efficient highly stereoselective methods for the synthesis of γ,δ-unsaturated,polyunsaturated carbonyl compounds and γ-lactonic aldehydes, but also thebasic transformations for a number of C-C bond formation reactions which can be usedto design synthesis of many acyclic, cyclic or polycyclic compounds.

本论文的主要工作分为两个部分:一、钯催化下炔烃的反应化学在本小组前人工作的基础上,我们详细研究了炔烃亲核钯化产生的烯基钯中间体与α,β-不饱和羰基化合物的反应,发现两价钯催化下卤离子-炔烃-α,β-不饱和醛酮的串联加成反应、卤离子-炔烃-α,β-不饱和醛酮的西组分串联加成及炔酸分子内氧钯化-串联Michael型加成反应;由此发展了γ,δ-不饱和醛酮、多不饱和羰基化合物和带有醛酮基侧链的γ-丁内酯衍生物的高立体选择性合成方法,这一过量卤离子存在下的烯基钯对α,β-不饱和羰基化合物共轭加成反应的发现,为大量碳-碳键形成反应的实现提供了基础,使我们能够从这一基本反应出发,设计和开发多种分子内、分子间的碳碳成键反应,以好的立体、区域选择性组建开链、环状及多环类型的化合物。

1 Heptane, it was revealed that the Cr〓/ Catsan and ZnCl〓 could catalyze the Michael addition of pyrrole with conjugate olefine at α-position of pyrrole to get mono- or bi-Michael addition product selectively under mild condition in good yield. Totally, forty-six new compounds, including thirty target compounds, were prepared.

在探索7-氮杂桥环母体的构建方法过程中,发现了Cr〓/Clay和ZnCl〓可有效地催化吡咯的α-位与多种共轭烯烃发生Michael加成反应,可在温和的条件下,以良好的收率选择性地得到单或双Michael加成产物。

The oxidations of-abietic acid by 〓,〓 and 〓 under various reaction conditions and its addition reaction withdichlorocarbene were investigated.

本文首先从广西产松香中分离纯化得到松香酸,然后探讨了不同条件下〓等氧化剂对其共轭双键的氧化反应以及二氧卡宾对其共轭双键的加成反应。

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推荐网络例句

They weren't aggressive, but I yelled and threw a rock in their direction to get them off the trail and away from me, just in case.

他们没有侵略性,但我大喊,并在他们的方向扔石头让他们过的线索,远离我,以防万一。

In slot 2 in your bag put wrapping paper, quantity does not matter in this case.

在你的书包里槽2把包装纸、数量无关紧要。

Store this product in a sealed, lightproof, dry and cool place.

密封,遮光,置阴凉干燥处。