乙酰乙酸乙酯

In our research on study chemical reaction of active methylene compounds and brom-acetophenone. Because of brom-acetophenone is compound that contain carbonyl and halogen ,which will take place electrophilic substitution and nucleophilic addition. When active methylene compounds are ethyl acetoacetate and β-diketone, controlling reaction condition, we have found that mono-substitution's production and di-substitution's. production is isolated; active methylene compounds are acetoacetanilide and acetoacetanilide derivate, pyrrolidin-2-one derivants were obtained by substitution and close-ring reaction .but there is no report about it.

本文是让活泼亚甲基类化合物与溴代苯乙酮发生化学反应，由于溴代苯乙酮是含有羰基的卤代烃结构，它可以发生亲电取代和亲核加成反应，当活泼亚甲基类化合物为乙酰乙酸乙酯和β-二酮时，控制反应条件可以发生单取代和双取代两种产物；当活泼亚甲基类化合物为乙酰乙酰芳胺类化合物来反应时，溴代苯乙酮中的羰基与氨基会发生分子内的关环反应生成吡咯烷-2-酮衍生物，这在以前的研究中是没有发现的。

Their specific surface area and acid strength were measured, and their catalyt and SBA-15 were ic performance was evaluated in the synthesis of fructone by acetalization of ethyl acetoacetate with ethylene glycol.

用浸渍法制备了一系列负载型磷钨酸及其铯盐催化剂，载体包括超稳Y沸石、脱铝超稳Y沸石、SiO2和SBA-15，测定了催化剂的比表面积和酸强度，并在乙酰乙酸乙酯与乙二醇液相缩合制取苹果酯反应中考察了催化剂的性能。

The strongly acidic cation exchange resin catalyzed synthesis of fructone-B by the reaction of ethyl acetoacetate and 1,2-propanediol was studied.

以硫酸高铈铵为催化剂，通过乙酰乙酸乙酯分别与乙二醇和1，2-丙二醇反应合成了苹果酯-A和苹果酯-B，研究了催化剂等有关因素对产品收率的影响。

Objective To determine the contents of residual acetone in acetoacetic ester,the raw material for the synthesis of Edaravone, by gas chromatography.Methods Sample solution was injected on a GDX column (0.18 mm～0.25 mm) with nitrogen as the carrier gas.The residue was calculated by the external standard method.

摘要］ 目的：用气相色谱法测定依达拉奉合成起始原料乙酰乙酸乙酯中丙酮的残留量方法：采用固定相二乙烯苯乙基乙烯苯型高分子孔小球（直径为0.18 mm～0.25 mm），氮气为载气，用外标法测定乙酰乙酸乙酯中残留丙酮的含量。

Formyl-3-acetyl-4-methyl-5-carbobenzoxypyrrole (6) was synthesized via the selective oxidation of 2,4-dimethyl-3-acetyl-5-carbobenzoxypyrrole (5), which was produced from acetylacetic benzylester (1) via nitrosation, reduction and addition-cyclization with acetylacetone. The total yield of the product was about 34%.

以乙酰乙酸苄酯(1)为原料，经过亚硝化、还原、与乙酰丙酮加成环化生成2， 4-二甲基－3-乙酰基－5-苄氧羰基吡咯(5)，通过选择性氧化反应制得目标化合物2-甲酰基－3-乙酰基－4-甲基－5-苄氧羰基吡咯(6)，反应的总收率约为34%。

Ethoxycarbonyl-4,5-dimethyl-pyrrole (7) was prepared from ethylacetoacetate, ethyl formate and methyl ethyl ketone via oximination, Claisen condensation, and reductive condensation. The bromization of compound 7 gave 2-ethoxycarbonyl-3-bromo-4,5-dimethyl-pyrrole(8), which could be transferred to 2-ethoxy-carbonyl-3-brome-4-methyl-5-formyl-pyrrole (9) by the formolation.

由乙酰乙酸乙酯、甲酸乙酯及丁酮等原料经过肟化、Claisen缩合、还原缩合成环得到2-乙氧羰基－4，5-二甲基－吡咯(7)，溴化生成2-乙氧羰基－3-溴4，5-二甲基－吡咯(8)，最后经过甲酰化反应得到目标产物2-乙氧羰基－3-溴－4-甲基－5-甲酰基－吡咯(9)。

The famciclovir was synthesized from purine by a series of steps by Acylation, Decarboxylation, Reduction ,and so on; Derivatives of these intermediates is described from the 6-chloro- 9H- purin-2-amine as raw materials in different conditions when the iodine and bromide were synthesized with the addition of two intermediate 6-bromo-9H-purin-2-amine and 6-iodo-9H-purin-2-amine; There is elaborated from the main part of a acetophenone, urineaminohydrochloride, phenylhydrazine, ethyl acetoacetate as raw material through a series of reactions to synthetic 3-phenyl-4-formylphenyl pyrazole and 5-chloro-3-methyl-1-phenyl-1H-pyrazole-4-aldehyde two pyrazole aldehyde, and then with 2-amino-6-chlorine-9-(2-methicillin-oxo-co-methyl-4-yl) purine reaction of the two new pyrazole purine Schiff bases.

本论文主是采用以鸟嘌呤为原料，经过一系列的酰基化，脱羧，还原等反应作用下最终得到了产物2-氨基-9-(4-乙酰氧基-3-乙酰氧基甲基丁基)嘌呤；其中的中间体衍生物主要是阐述从以2-氨基-6-氯鸟嘌呤为原料通过在不同的条件下进行溴代与碘代分别合成了另外两种中间体2-氨基-6-溴鸟嘌呤及2-氨基-6-碘鸟嘌呤；还有一部分主要是阐述从以苯乙酮，盐酸氨基脲，苯肼，乙酰乙酸乙酯为原料通过一系列的反应先合成3-苯基-4-醛基吡唑及5-氯-3-甲基-1-苯基-1H-吡唑-4-甲醛这两个吡唑醛，然后再与2-氨基-6-氯-9-(2-甲氧羰基丁酸甲酯-4-基)嘌呤反应得到了两个新型的吡唑嘌呤席夫碱

Using silicotungstic acid as catalyst with the catalyst supported on active carbon,2-methyl-2-ethyl-acetic-1,3-oxathiolane(targeted compound I,an aroma compound with apple flavor )was synthesized by the reaction of ethyl aceto-acetate and 2-mercapto-ethanol.

以活性炭固载硅钨酸作为催化剂，用乙酰乙酸乙酯与巯基乙醇缩和合成了具有浓郁苹果香气的香料化合物2-甲基-2-乙酸乙酯基-1，3-氧硫杂环戊烷。

Bromo-5-formyl -3-methylpyrrole is an important intermediate of tolyporohin. On the base of introducing the present research and development of tolypo- rohin and pyrroles ramification at home and abroad, an emphasis was made on synthesis of 2-Bromo-5-formyl -3-methylpyrrole and the technical conditions of all steps, which was described as follows. Diethyl 3,5-dimethylpyrrole-2,4-dicarboxylate was made by nitrification, reduction and cycle of ethyl acetoacetate.

由于2-溴-5-甲酰基-3-甲基吡咯是合成托尼卟吩的重要中间体，本文在阐述了当前托尼卟吩及吡咯衍生物的国内外研究和开发的基础上，重点研究了2-溴-5-甲酰基-3-甲基吡咯的合成，并对各步反应进行了工艺研究，具体合成步骤如下：本文通过对乙酰乙酸乙酯的亚硝化、还原、成环，反应生成吡咯单环衍生物2，4-二乙氧羰基-3，5-二甲基吡咯。

Dihydropyrimidin-2 (1H)-ones were synthesized by condensation of aromatic or aliphatic aldehydes, urea and ethyl acetoacetate or acetylacetone one-pot three-component Biginelli condensation in the presence of room temperature ionic liquids as catalysts under solvent-free conditions.

5利用室温离子液体作催化剂，芳香或脂肪醛、尿素和乙酰乙酸乙酯或乙酰丙酮三组分缩合制备3，4-二氢嘧啶-2-酮衍生物。

The objective is to subjugate and discourage the people, because that allows the elite to continue to rule unopposed.

其目的是压制和打击人民的积极性，因为这可以让实权派继续统治不会沦为反对派。

GOD,this is the second time you vanquished me!

天啊，这是第二次你打败了我！