酮式烯酮

The crystal structures of them show the photochromism is due to the photoisomerization only from enol form to keto form. According to the results of structure analyses, the intermolecular proton transfer mechanism is proposed for photochromism. We also observed their acidichromism in solution.

采用单晶XRD法得到了这五种化合物的结构，根据结构解析，推测四种光致变色化合物的变色机理可能是分子间质子转移，即吡唑啉酮由烯醇式结构变为酮式结构。

The clarification, coordination modes of keto and enol form and of mono and multidentate, properties of biological and pharmacoligical activities and nonlinear optical of acylhydrazone compounds are reviewed.

综述酰腙化合物的种类，酮式、烯醇式、单齿和多齿配位形式，生物和药物活性及非线性光学性质

The integrated analytical results show that the novel ligand coexists in ketoform and enolform structures under the measuring conditions, the ketoform structure may change into the enolform structure during the coordination and bonds with the central ion by two O atoms of the enolized hydroxyl group of pyrazolone ring and H2O and the N atom of the imine group and the N atom containing H of benzimidazole ring by losing the proton. And the coordination number of these complexes is four.

综合各种分析结果显示：配体在测试条件下以酮式和烯醇式结构共存，配位时酮式可能转化为烯醇式结构，按去质子的方式以吡唑啉酮环羟基和H2O上的两个O原子以及亚胺基上的N原子和苯并咪唑环上的含氢N原子与中心离子成键，配合物的配位数为4。

15K. It is shown that two main factors, pressure and the polarity of the mixture, influence the EAA tautomerism.

结果表明，EAA的酮式-烯醇式异构化平衡常数随共溶剂极性的增加而减小。

Master the Keto-Enol tautomerism; reactions of enols:α-H substitution reactions;α-halogenation of aldehydes and ketones;α-bromination of carboxylic acids; acidity ofα-H atoms: enolate ion formation; reactivity of enolate ions; alkylation of enolate ions; mechanism of carbonyl condensation reactions;condensations of aldehydes and ketones: the Aldol reaction; dehydration of Aldol products; the Claisen condensation reaction; the Michael addition.

熟练掌握酮式－烯醇式互变异构；烯醇的反应：α-H的活性；醛酮的α卤代反应；羧酸的α-溴代反应；α-H的酸性：烯醇负离子的形成；烯醇负离子的反应；烯醇负离子的烃基化；羰基化合物的缩合反应机理；醛酮的缩合反应－Aldol缩合；Aldol缩合产物的脱水反应； Cleisen 酯缩合反应；麦克尔加成反应。

So, by the Diels-Alder reaction of tetraphenylcyclopentadienone, acenaphthenecyclone and benzophenanthrenecyclone with the vinyl groups in C gum, three kinds of polymethylvinylsilicone oil with condensed aromatics are synthesized respectively: polymethylvinylsilicone oil with tetraphenylphenyl groups (called C_1 gum for short), polymethylvinylsilicone oil with acenaphthenyl groups (C_2 gum) and polymethylvinylsilicone oil with benzophenanthrene groups (C3 gum).

根据此原则，利用四苯基环戊二烯酮、苊式环戊二烯酮和菲式环戊二烯酮与C胶上的乙烯基进行Diels—Alder反应，分别合成了三种含稠环基团的乙烯基硅油：四苯基苯基乙烯基硅油(C_1胶)，苊式多苯基苯基乙烯基硅油(C_2胶)和菲式多苯基苯基乙烯基硅油(C_3胶)，并根据~1HNMR谱图上不同氢原子的积分面积计算了三种胶中稠环基团和乙烯基的含量。

The simulation results show that the free energy of hydrogenation of acetylacetone iron to prepare enol-acetylacetone is less than that of the reaction to produce keto-acetylacetone at the same temperature.

计算结果表明：相同温度下，乙酰丙酮铁加氢生成烯醇式乙酰丙酮的反应自由能小于生成酮式结构乙酰丙酮的反应自由能；乙酰丙酮铁加氢更倾向于生成烯醇式结构的产物。

Its mechanism is the use of anthraquinone in alkali conditions off proton surface forming 10 more stable carbon anion face, but because carbon anion and oxygen ion exist between testosterone and enolate type each other changes, cause reaction product complex, at least five, reaction selectivity, product yield, separation difficulties, and product purity is not high, therefore, using the type and quantity of alkali, phase transfer catalyst type, solvent, to optimize the selection process conditions so as to improve the yield target product.

其机理是利用蒽酮在碱存在的条件下脱去氢质子面形成10位较稳定的碳负离子面进行，但是因为碳负离子和氧负离子之间存在酮式和烯醇式的互变，导致反应复杂，产物至少有五种，反应选择性差，产物分离困难，产率低，且产品纯度不高，因此，利用对碱的种类和量的多少，相转移催化剂的种类，反应溶剂的选择，来优化反应工艺条件从而提高目标产物的产率。

The reaction of cyclic b-keto esters with CF3CO2ZnCH2I provides the corresponding ring-expanded products with the advantage of mild condition in moderate to good yields. A simple and efficient procedure has been developed for a variety of 1,3-diketones converted into the corresponding 1,4-diketones and trans-1,2-disubstituted cyclopropanols in high yields. In conclusion, this new type of organozinc reagents has been developed for many useful reaction in organic synthesis.

利用有机锌试剂所具有的双重特性，在新型的Baylis-Hillman反应中，可以直接与炔基酮和醛反应一锅制得多官能团的三取代的顺式烯；在b-酮酯化合物的扩环反应中，取得了重要进展，得到了增加一个碳的扩环产物，&一步法&合成，反应条件温和、环境友好；在1，3-二酮分子中成功地插入1个碳，合成出1，4-二酮和环丙醇，为现代有机合成提供了新的合成方法，具有良好的应用前景。

According to the results of the examination, the stronger the electron-withdrawing protective group of imines, the better the cis-selectivity of the reaction, 68% yield, trans:cis is 99:1 diastereoselectivity could be leaded by Ts-imines (4-methyl-N-methylene-benzenesulfonaides) with a substituent [2,4-(CH3O)2C6H3], Substrate scope investigation revealed that a wide variety of ketenes and imines could react smoothly to afford corresponding,β-lactams.

实验结果表明，亚胺的保护基团吸电子能力越强，越有利于顺式产物的生成。对甲苯磺酰基保护的取代基为2，4-二甲氧苯基的亚胺参与的该反应可得到68%的产率，反式：顺式=99：1的非对映选择性。底物拓展过程中发现Staudinger反应适用于多种不同的亚胺与烯酮。

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。