缩酮

In the first step of thedouble annulation route, 2-amino-3-carbamoyl-5,6-dihydro-4-pyridones 2 werecreated in high to excellent yields by a formal [5C + 1N] annulation reaction ofketene--acetals 1 with ammonia.

第一步，二硫缩烯酮1和氨源通过[5C + 1N]加成反应产率极高的得到了2-氨基-3-氨基甲酰基-5，6-二氢-4-吡啶酮2。

In this paper, Claisen condensation of isochroman ?4?one as starting material with diethyl oxalate is carried out to form β?diketone compound of isochroman ?4?one.

以异色满酮 4为起始原料，经Claisen缩合得其β二酮衍生物，再与水合肼进行Knorr反应环合成 3 乙氧甲酰基和 3 肼甲酰基异色满并吡唑衍生物，通过酰肼与糠醛反应成腙后，分别与巯基乙酸和氯乙酰氯反应合成了标题化合物

Methods The propylbridged biferrocenyl substituted pyridazinone was synthesized by the reaction of propylbridged biferrocene with ethyl succinyl chloride, and then condensed with hydrazine hydrate.

双二茂铁丙烷先与丁二酸单乙酯酰氯发生酰化反应，生成的1，4酮酸酯再与水合肼缩合得到含有双二茂铁丙烷的哒嗪酮衍生物。

Second, we investigated the aldol reactions of the specialα-oxo ketene dithioacetals with aromatic aldehydes under the mild conditions in good yields.

在温和的条件(室温、30℃)下，高产率地实现了α-羰基二硫缩烯酮与芳香醛的缩合反应。3。

In this paper, a series of 4,5-dithiacrown ether annulated 1,3-dithiole-2-thiones 8a~8d were prepared via condensing 4,5-bis-1,3-dithiole-2-thione (7) with 1,ω-dimercapto polyglycol derivatives in high dilution. The obvious template effect was found during the synthesis of 8c-8d.

在高度稀释条件下，经4，5-二溴甲基-1，3-二硫杂环戊烯-2-硫酮(7)和多缩乙二醇的1，ω-二巯基衍生物的缩合反应，方便地合成了4，5-位带二硫杂冠醚残基的2-硫代-1，3-二硫杂环戊烯的衍生物8a~8d，中间体硫杂冠醚8c~8d的合成中有明显的&模板效应&。

In this paper, a series of 4,5-dithiacrown ether annulated 1,3-dithiole-2-thiones 8a~8d were prepared via condensing 4,5-bis-1,3-dithiole-2-thione (7) with 1,ω-dimercapto polyglycol derivatives in high dilution. The obvious template effect was found during the synthesis of 8c-8d.

在高度稀释条件下，经4，5-二溴甲基-1，3-二硫杂环戊烯-2-硫酮(7)和多缩乙二醇的1，ω-二巰基衍生物的缩合反应，方便地合成了4，5-位带二硫杂冠醚残基的2-硫代-1，3-二硫杂环戊烯的衍生物8a~8d，中间体硫杂冠醚8c~8d的合成中有明显的&模板效应&。

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)。

Four chalcones were synthesized by aldol condensation reaction of acetophenone or para-substituted acetophenones with 2-phenyl-1,2,3-triazol-4-carboxaldehyde, which reacted with three hydrazines in glacial acetic acid under refluxing to give a series of pyrazoline derivatives.

以2-苯基－1，2，3-三唑基－4-甲醛为原料，与苯乙酮［或取代苯乙酮(1a~1d)］发生羟醛缩合，生成相应的查尔酮(2a~2d)，再与不同的肼反应，合成了12种新的5位含2-苯基－1，2，3-三唑基的吡唑啉衍生物3a~3d，4a~4d，5a~5d。

In order to study the aldol condensation of 2.15-hexadecanedione on the surface of aluminium, the intermolecular condensation mechanism of acetone occurring on aluminum was simulated by using semi-empirical AM1 method embodied in MOPAC 6.0 program package. The optimized structures and geometry parameters of 5 transition complexes and 4 intermediates were given.First, 2 molecules of acetone coordinated with aluminum by electrostatic attraction.One atom of hydrogen of acetone migrated to aluminum because of t...

为了研究2，15－十六烷二酮在氧化铝表面的环合机理，选择小分子丙酮为模型化合物，用量子化学半经验AM1方法研究双分子丙酮在氧化铝表面的醛醇缩合机理，给出了反应过程中的5个过渡态和4个中间体的结构和几何参数，该催化反应可以认为是氧化铝分子与两分子丙酮分子发生静电络合作用，然后借助氧原子的负电荷导致脱氢并实现缩合，根据中间体的能量变化，推测有较稳定的铝复合物生成。

Methyl isobutyl ketone is a good origanic slovent and the advanced process for producing MIBK is one-step synthesis by gas-phase condensation and hydrogenation of acetone. In this process, the key technology is to develop the multi-fuctional catalyst, which has both the ability of hydrogenateon and condensation, as well as suitable acid-base sites.

甲基异丁基酮是一种优良的有机溶剂，先进的生产方法是丙酮气相缩合加氢一步法，该工艺关键的技术是开发高效的双功能催化剂，即催化剂同时具有缩合、加氢以及适宜的酸、碱性质。

I am accused of being overreligious," she said in her quiet, frank manner,"but that does not prevent me thinking the children very cruel who obstinately commit such suicide.""

客人们在卡罗利娜·埃凯家里，举止就文雅一些，因为卡罗利娜的母亲治家很严厉。

Designed by French fashion house Herm è s, this elegant uniform was manufactured in our home, Hong Kong, and was the first without a hat.

由著名品牌 Herm è s 设计，这件高贵的制服是香港本土制造，是我们第一套不配帽子的制服。