查询词典 cyanoacetate

As to the catalytic coupling of aryl bromides, when triphenylphosphine as ligand and malononitrile as subtracts, their isolated yields were generally in 72-88%; While using cyanoacetate instead of malononitrile, the yields were in 67-84%.

当采用常见的三苯基膦为配体、对取代溴苯而言，以丙二腈为底物时，偶联产物的分离产率一般都在72-88％之间；以腈基乙酸乙酯为底物时，分离产率在67-84％之间。

The condensation of aromatic aldehydes with active methylene compounds like malononitrile, cyanoacetamide and ethyl cyanoacetate has been found to proceed very efficiently at room temperature giving excellent yields, but the condensation of heteroaromatic,α,β-unsaturated and aliphatic aldehydes with active methylene compounds proceeded smoothly in 50~65℃ with good yields and the reactions of aromatic, aliphatic ketones as well as p-phthalaldehyde with malononitrile also proceeded in 75~85℃ with moderate yields.

芳香醛与活泼亚甲基化合物如丙二腈、氰基乙酸乙酯、氰基乙酰胺的缩合在室温下即能顺利进行，获得了很高的收率；而对于杂环芳醛、α，β-不饱和的醛以及脂肪醛与活泼亚甲基化合物的缩合，需在50~65℃下进行，也取得了很高的收率；对于脂肪酮、芳香酮以及二元醛与丙二腈的缩合在75~85℃下也能顺利地进行，获得中等以上的收率。

Knoevenagel condensation reaction between aromatic aldehyde, malononitrile or ethyl cyanoacetate is promoted by organocatalyst N-methylimidazole.

以1-甲基咪唑为有机小分子催化剂催化芳香醛与丙二腈或氰乙酸乙酯的Knoevenagel缩合反应，反应速度快，操作方便，产率高，后处理简单。

Knoevenagel condensation reaction of aromatic aldehydes with active methylene compounds like ethyl cyanoacetate proceeds smoothly in water in the presence of 8mol% of diammonium hydrogen phosphate and 2mol% TEBA.

醛与活泼亚甲基化合物的 Knoevenagel 反应是有机合成中广泛应用的形成碳碳键的重要方法，该反应一般是弱碱性催化剂存在下完成的，如各类胺、脲[1]等，Lerwis酸[2]、杂多酸[3]、氨基酸[4]等也可用于催化该反应。

Based on the problem of various types of catalyst and according to the features of carbonylation catalysts reactions, our team has been designed a series of new metal complexes of benimidazoles, which can be used for carbonylation catalyst of industry. Seven new benzimidazole derivatives were prepared by the o-phenylenediamine、oxalic acid、glycolic acid、monomethyl monopotassium malonate、ethyl cyanoacetate、succinic anhydride. The structures of them were confirmed by IR、Elemental analsis. The crystal structures of d and e were determined by X-ray single crystal diffraction of Germanic Bruker Smart APEX II CCD. The catalysis of them was tested by carbonylation reactions.

本文设计以邻苯二胺和草酸、羟基乙酸、丙二酸单甲酯、氰基乙酸乙酯、丁二酸单甲酯为原料采用PPA催化和无机酸催化法，合成了4种苯并咪唑-2-羧酸衍生物并进行了表征；培养了2个化合物d、e的晶体并测定和讨论了晶体结构；制备了3种未见报道的苯并咪唑金属配合物，对配合物在羰基化法制醋酐-醋酸反应的催化作用进行了初步试验。

METHODS 5-amino-1-hydroxyethyl pyrazole-4-carboylic acid was synthesized through condensation of ethyl cyanoacetate and triethyl orthoformate followed by one-pot methodology of cyclization,hydolysis.

方法原甲酸三乙酯与氰乙酸乙酯缩合，然后和羟乙基肼经环合、水解等一锅法合成5-氨基吡唑-4-甲酸，然后在亚硫酸钠存在条件下加热脱羧得到5-氨基-1-羟乙基吡唑。

Using ethyl cyanoacetate , triethyl orthoformate and methylhydrazine as main raw materials, the herbicide pyrazosulfuron was prepared through the reactions of substitution, amination, cylclization, diazotization and chlorosulfonation.

以氰乙酸乙酯、原甲酸三乙酯和甲肼等为主要原料，通过取代、胺化、环化、重氮化和氯磺化等反应制得了除草剂吡嘧磺隆原料药。

Starting with two reactive methylene compounds, ethyl cyanoacetate and malononitrile, two 5-amino-1H-pyrazoles were prepared through the intermediates ketene dithioacetal.

从两个活泼亚甲基化合物开始，经过乙烯酮二硫代缩醛中间体，合成了两个5-氨基-1H-吡唑，以这个两个化合物为中间体，与芳香族和脂肪族α-溴代酮反应，而后经酸催化亚胺化互变异构后得到含咪唑并[1，2-b]吡唑甲硫醚类化合物6a-6g。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。