查询词典 reaction

In chapter four, the preperation of ytterbium diiodide was examined. The reductive cleavage of Se-Se bond and S-S bond induced by ytterbium diiodide was investigated. The reaction of diselenides and disulfides with allylic bromide promoted by ytterbium diiodide was also examined. The intermolecular Barbier-type reaction induced by ytterbium diiodide was studied. In the last section of this chapter, the intermolecular reductive coupling of nitriles with azides induced by samarium diiodide was investigated.

第四章，研究了二碘化镱的制备方法，以及二碘化镱作为一种优良的单电子转移试剂在有机合成中的应用：二硒醚的Se--Se键和二硫醚S-S键的还原断裂，及其在合成烯丙基硒醚，硒代酯和烯丙基硫醚，硫代酯中的应用，实验结果表明二碘化镱也能促进分子间的Barbier反应，而文献认为二碘化镱不能促进分子间的Barbier反应；最后研究了二碘化钐促进的叠氮化合物与腈的交叉还原偶联反应，一步高收率地制备脒的方法。

The chapter two was focused on the samarium diiodide promoted organic reactions and their applications in organic synthesis, firstly, a new synthesis of highly substituted cyclopentadienes from a,β-alkynone promoted by samarium diiodide was investigated and the highly substituted cyclopentadienes were prepared in moderate to good yields under mild conditions. Secondly, the Michael addition and Michael-aldol tandem reaction of diorganyl diselenides or diorganyl disulfides with α,β-alkynones mediated by samarium diiodide were studied and a series of alkenylsulfides and alkenylselenides were prepared in good yields. Then the highly regioselecfive nucleophilic addition of the allylsamarium bromide to α,β-alkynones were explored. We found that the allylsamarium bromide reacts with α,β-alkynones to afford regiospecificly 1. 2-nucleophilic addition products in good yields under mild condition. At last we studied the coupling reaction of aryl halides promoted by NiCl〓/PPh〓/Sm〓.

第二章 研究了二碘化钐、金属钐促进的有机反应：1、二碘化钐促进下α，β-炔基酮的偶联环化反应，提供了一种制备多取代环戊二烯的新方法；2、二碘化钐促进下的二硫醚、二硒醚与α，β-炔基酮的Michael加成反应，为高产率地制备多取代的烯基硫或烯基硒化合物提供了方便可靠的新方法；3、二碘化钐促进下的二硫醚、二硒醚与α，β-炔基酮和醛、酮的Michael—aldol串联反应，提供了一种一锅法高产率地制备多取代的含硫的烯丙基醇或含硒的烯丙基醇类化合物的方便可靠的原子经济性的新方法；4、烯丙基溴化钐与α，β-炔基酮的高度区域选择性的1，2-亲核加成反应；5、NiCl〓/PPh〓/Sm〓促进的卤代芳烃的偶联反应-一种从各种卤代芳烃制备联苯类化合物的有效方法。

This reaction was further extended to the coupling reaction of amide with diiodo biphenyl; and the carbazole derivatives were synthesized in 53%-95% yield.

另外将该反应体系的底物进行了进一步的拓展，用酰胺和二碘代联苯化合物偶联，合成了9个咔唑衍生物，收率在53％—95％之间，并运用~1H NMR、~(13)C NMR、HRMS等分析测试手段对这些化合物进行了表征。

Methods Carry out mfVEP detection to 30 AION (30 eyes) analysis second order kernel .The reaction was divided to dimidiate and quartered field .Analysis the sum totol waves of every reaction ,to compare every sector ,primary compare the waveshape characreristic with AION eyes and fellow eyes or treatment circa of AION eye.

对30例AION患者(30只眼)进行多焦VEP检测，主要分析mfVEP的二阶反应，将反应分上、下半侧视野，1/4象限视野(鼻上、鼻下、颞上、颞下)，分析各反应总和波，对各区域进行比较，主要比较AION眼与对侧眼及AION眼治疗前后各部分的波形特征。

Prolonging nitration time and increasing reaction temperature would promote the formation of dinitro products while shortening the nitration time and decreasing reaction temperature would promote the formation of mono-nitro products.

延长反应时间和提高反应温度有利于二硝化产物的形成，缩短反应时间和降低反应温度有利于单硝化产物的形成。

From comparative research of synchronous and asynchronous reaction of dehydrogenation and cracking of dipentene,it is shown that farraginous extent of by-products from synchronous reaction is relatively high.

双戊烯脱氢裂解的同步反应和异步反应对比研究显示，双戊烯脱氢裂解的同步反应产物比较混杂，反应产物中甲苯的相对含量仅为24。

From comparative research of synchronous and asynchronous reaction of dehydrogenation and cracking of dipentene,it is shown that farraginous extent of by-products from synchronous reaction is relatively high.

双戊烯脱氢裂解的同步反应和异步反应对比研究显示，双戊烯脱氢裂解的同步反应产物比较混杂，反应产物中甲苯的相对含量仅为24.03%，双戊烯相对于甲苯的料耗比为5.34，甲苯的得率为30.79%，中间产物对伞花烃的得率为2.49%；双戊烯脱氢裂解的异步反应产物混杂程度相对较低，反应产物中甲苯的相对含量为40.74%，对伞花烃的相对含量为18.31%，双戊烯相对于甲苯的料耗比为3.33，甲苯的得率为49.26%，中间产物对伞花烃的得率为16.92%。

The epoxide-terminated oligomer having ether mesogenic unit wassynthesized for the first time by reacting the diphenol with epichlorohydrin. Theepoxy equivalent increased as the elongation of reaction time or the decrease of theinitial ratio of diphenol and epichlorohydrin, but effect of the reaction time wassmaller than that of the initial ratio.

首次采用直接环氧化的方法合成了含酯类液晶基元的环氧结构预聚物，环氧化反应中反应配比和反应时间会影响产物的环氧当量；缩小反应配比或延长反应时间会使产物的环氧当量增大，反应时间对产物环氧当量的影响较小。5。

Dipolar cycloaddition reaction is the most useful reaction in fundmental theory of organic chemistry and organic synthesis.

1，3-偶极环加成反应是有机化学基础理论及合成方法研究中起重要作用的一个反应。

The function process of this kind of additives is that the additives discomposing reaction can occur before the electrolytes do at the first charge-discharge cycle, forming a fine SEI film, and avoiding or decreasing the discomposing reaction of electrolytes.

在首次充电过程中，添加剂首先发生还原分解反应，形成一层良好的SEI膜，从而避免和减少电解液的还原分解。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。