共查询到20条相似文献,搜索用时 219 毫秒
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乙二胺衍生物的新合成法 总被引:2,自引:0,他引:2
乙二胺衍生物的新合成法史真,王建华,赵莉,卢心中(西北大学化学系,西安710069)(陕西教育学院化学系,西安710061)乙二胺衍生物是合成表面活性剂、抗静电剂、柔软剂、杀菌剂的重要中间体[1,2],研究其新的简便的合成方法有重要意义。作者曾首次提... 相似文献
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几个新型二茂铁衍生物的合成 总被引:3,自引:0,他引:3
二茂铁及其衍生物作为油类消烟剂、燃速催化剂等已得到应用,在药物、合成材料等方面亦具有应用前景。文献曾报道含二茂铁基β-二酮的合成及以它为配体的金属配合物。此类配合物均含两个以上金属原子,它们在有机合成中具有独特的催化活性。 我们将二茂铁甲酰丙酮分别与水扬酰肼、异菸肼、乙二胺及硫代氨基脲在甲醇或甲醇-水介质中进行缩合反应,合成了4个新型二茂铁衍生物,它们含有三个或四个配位功能基团,可作为多齿配体用于金属有机配合物的合成。衍生物的合成路线如下: 相似文献
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A new reduction ring-opening reaction of 2-imidazoline with sodium borohydride is reported, and the effect of reaction condition on the yield, reaction mechanism and the use of the new reaction in synthesis of ethylenediamine derivatives are discussed. A new method for the preparation of unsymmetrical substituted ethylenediamine via the reduction ring-opening reaction of imidazoline is provided. 相似文献
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报道了一种制备α-羟醛的未见文献报道的合成方法, 以乙二胺和α-羟基羧酸为原料, 经咪唑啉中间体, 得到α-羟醛。讨论了反应条件、取代基对咪唑啉中间体还原水解反应产率的影响。 相似文献
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1,4-Diarylimidazoline 3-oxides react with N-arylmaleimides in benzene to give predominantly the corresponding endo adducts. Chiral imidazoline 3-oxides react diastereospecifically (cis configuration of the tetrahydroimidazo ring) and diastereoselectively to give cis-endo adducts. The effects of substituents on the aromatic ring of the maleimide was investigated. The presence of electron-withdrawing or releasing groups have minor effect on the total yields but more pronounced is the effect on the ratio of exo and endo diastereomers. The adducts undergo an interesting and unprecedented ring-opening in the presence of secondary amines to give deoxygenated 3-imidazoline 3-oxides instead of the expected double cis elimination products. Tertiary amines did not induce any reaction. 相似文献
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TS-1催化丙烯环氧化过程中环氧丙烷的开环反应研究 总被引:3,自引:1,他引:3
环氧丙烷的开环反应是TS-1催化丙烯环氧化制备环氧丙烷过程的副反应,本文对醇溶剂中开环反应进行了研究,分析了该反应的酸性催化机理,酸性主要来自TS-1与H2O2的相互作用产生的质子酸,醇溶剂能显著增强体系酸性从而加快环氧丙烷的开环反应速度。三种醇按酸性增强程度的顺序为甲醇>异丙醇>仲丁醇。根据反应的Eley-Rideal 机理(吸附态的PO与游离态的醇发生开环反应,表面反应为控制步骤)再考虑各组分在TS-1上的吸附特点提出反应的机理模型。用实验数据进行了回归,得到了令人满意的动力学方程式,实验数据与模型计算值平均偏差小于10%。 相似文献
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Yuan DQ Tahara T Chen WH Okabe Y Yang C Yagi Y Nogami Y Fukudome M Fujita K 《The Journal of organic chemistry》2003,68(24):9456-9466
Three types of reactions of 2,3-anhydro-beta-cyclodextrins, namely nucleophilic ring-opening, reduction to 2-enopyranose, and reduction to 3-deoxypyranose, have been investigated to regio- and stereoselectively functionalize the secondary face of beta-cyclodextrin. Upon treatment with various nucleophiles, both 2,3-mannoepoxy and 2,3-alloepoxy-beta-cyclodextrins are found to undergo nucleophilic ring-opening reaction generating 3- and 2-modified cyclodextrin derivatives. In each case, the 3-position is more easily accessible than the 2-position. By using these ring-opening reactions, imidazolyl, iodo, azido, and benzylmercapto groups are selectively introduced to the secondary face of beta-cyclodextrin in place of the 2- or 3-hydroxyl groups. The functionalized cyclodextrins have either modified glucosidic subunits or modified altrosidic subunits that make the hydrophobic cavity slightly distorted from that of native beta-cyclodextrin. Thiourea also reacts with the cyclodextrin epoxides. In this case, thiirane and olefin species are generated instead of any ring-opening products. By ameliorating the reaction condition, cyclodextrin olefin, diene, and triene derivatives are prepared in moderate to good yields. Reduction of per[6-(tert-butyldimethyl)silyl]-beta-cyclodextrin permannoepoxide with lithium aluminum hydride produces the per(3-deoxy)-beta-cyclomannin. All these chemically modified cyclodextrins are structurally well characterized and most of them are expected to serve as versatile scaffolds for diverse purposes such as the construction of catalysts and development of synthetic receptors and molecular containers. 相似文献