查询词典 reaction ring

The theoretical properties of BTATz were estimated by a B3LYP method based on 6-31G basis set. The stable geometric configuration and bond order were obtained. The vibrational frequencies, IR spectrum and thermodynamics properties under different temperatures were obtained from vibrational analysis, and the relationship between temperature and thermodynamics properties was deducted. Pyrolysis mechanism of BTATz was discussed, and the transition state and activation energy of ring opening reaction of the tetrazole were deducted.

用B3LYP方法，在6-31G基组水平上对其性能进行了计算，得到了其稳定的几何构型和键级；在振动分析的基础上求得体系的振动频率、IR谱及不同温度下的热力学性质，并得到了温度对热力学性能影响的关系式；探讨了其热解机理，推断出四唑环开环时的过渡态和活化能。

The target compound was cut off from the middle of the two benzene ring of Biphenyl Tetrazole and the key step was accomplished through Suzuki Coupling reaction.

第二部分：抗高血压药物——缬沙坦的新合成路线研究我们分别以对溴甲苯，对溴苄溴和对溴苯甲醛为起始原料分三条路线完成了缬沙坦的全合成。

A novel BB'2-type aromatic triamine containing pyridine ring was successfully synthesized by catalytic reduction of the trinitro compound obtained by a modified Chichibabin reaction in acidic medium with hydrazine hydrate.

采用商品化的原料，在酸性介质中经改进的Chichibabin反应先合成含吡啶环的三硝基化合物，再用水合肼催化还原得到一种新型的含吡啶环BB'2型芳香三胺单体。

In addition, we found that 4-phenyl-l,2,4-triazolinium N-ylides reacted withvarious electron-deficient olefins to afford pyrrole derivatives in good yields via 1,3-dipolar cycloaddition oxidative ring fission, In some cases, tetrahydropyrrolo[1,2-b]triazole and pyrrolo[1,2-b]triazole, which are stable and are not aromatized orcleaved in the reaction conditions, could be isolated, This is a facile and novel route forthe synthesis of pyrrole derivatives.

此外，本文研究了五员三氮杂环化合物4-苯基1，2，4-三氮唑的N-叶立德，发现在氧化剂存在下与缺电子烯烃发生1，3-偶极环加成反应生成的吡咯并[1，2-b]三氮唑，在大多数情况下开环生成吡咯衍生物，反应条件温和，收率良好，是合成吡咯衍生物的一个新的途径。

Methods: 2-ethyl aniline was used as starting material of the synthesis and was processed by acetic anhydride acylation, strong nitric acid nitraction at low temperature, and desacyl synthesis to produce 2-ethyl-5-nitro aniline. The product was then synthesized to 3-methyl-6-nitro-lH-indazole by using ring-closing reaction in the presence of NaNO2, and then ethylated to obtain 2, 3-diethyl-6- nitro-2H-indazole. The latter compound was then reduced by SnC12/Hcl to get target compound 2, 3-diethyl-6-nitro-2H-indazole.

以2-乙基苯胺为原料经醋酐酰化、浓硝酸低温硝化及去酰基保护合成2-乙基－5-硝基苯胺，后用亚硝酸钠关环得3-甲基－6-硝基－1H-吲唑，经硫酸二甲酯甲基化得2，3-二甲基－6-硝基－2H-吲唑，最后用氯化亚锡将其还原得到目标产物，通过1HNMR确定结构与目标产物一致。

The application, proposed hydrotalcite-like compounds as a new type of environmentally friendly solid catalysts in the aldol condensation, nitrile hydrolysis, epoxide ring-opening reaction of the oxidation of aromatic compounds, alcohols oxidation, reduction of nitro compounds, and many other important reactions in organic synthesis has an important application potential, and with little pollution compared to conventional catalysts, easy separation of advantages of high reactivity.

叙述了水滑石类化合物作为固体酸碱催化剂、氧化还原反应催化剂、催化剂载体等方面的应用情况，提出了水滑石类化合物作为一类新型的环境友好的固体催化剂，在醇醛缩合、腈类水解、环氧化物的开环反应、芳烃类化合物的氧化、醇类氧化、硝基化合物的还原等许多重要的有机合成反应具有重要的应用前景，并且与传统催化剂相比具有污染小、易分离、反应活性高等优点。

To dye the different types of fibers by the same dye, universal dyes based on naphthalene ring system are prepared by the diazo coupling reaction of 7-acetamide-4-hydroxy-2-oaphtialene-β-(N,N-dimethylaminoethyl)solfonamide and m-aminobenzene-β-hydroxyethyl sulfone sulfunate.

为了实现用同一支染料对不同类型的纤维进行染色的目的，通过间氨基苯基－β-羟乙基砜硫酸酯与7-乙酰氨基－4-羟基－2-萘－β磺酰胺的重氮化偶合反应合成了含萘环的通用染料，其结构通过质谱分析进行了表征。

This thesis is concerned with studies on the ring opening reaction catalyzed by gold catalysis via carbon-carbon bond cleavages.

本文主要研究了金催化碳碳键断裂的开环反应，全文共分为三个部分：第一章：对均相金催化研究进行了总结，综述了均相金催化的研究进展。

On the basis of our preceding work. the asymmetric ring-opening reaction of epoxides using dithiophosphorus acids as nucleophiles was further studied.

在本课题组已有工作的基础上，我们对磷试剂参与的环氧化合物的不对称开环反应进行了进一步的研究。

The application of them as catalysts in the asymmetric ring-opening of epoxides was investigated. Through the screening of the catalysts, we found that some of them demonstrated good asymmetric induction ability in this reaction.

我们对非手性二硫代磷酸在手性Schiff碱和Ti〓的存在下对环氧化合物的不对称开环反应进行了研究，对手性Schiff碱进行了进一步的筛选。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。