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报道了一个4,6-二甲氧基嘧啶取代的硫脲的分子结构和二维构筑体系.在这个分子中,通过强分子内氢键锁硫脲的3个主要片段促使分子呈现近平面结构;不同类型的弱分子间C-H—S和C-H—O氢键导致分子形成不同类型的二聚单元;这些二聚单元结合分子间的偶极-偶极促使分子呈现不同类型的席状体系;另外,π-π堆积和氯/氯间紧密相互作用导致嘧啶取代的硫脲分子呈现高度有序的交错层的自聚集体系.  相似文献   
2.
不对称催化是有机化学研究的前沿领域和发展方向.近10年来,手性配体的研究得到了长足的发展,大量的小分子手性配体被报道,其中许多手性配体展示了优异的催化性能.但是由于昂贵的手性配体(金属催化剂)分离、回收和再利用的问题,从而限制了小分子催化剂的应用.因此,解决手性金属催化剂的分离与回收问题是不对称催化研究领域的一个热点问题.为了解决这一关键问题,国内外科学家从负载的角度出发已经成功地发展了众多的研究方法,无机负载法、交联高分子负载法、可溶性高分子负载法、树状大分子负载法等.许多负载的手性金属催化剂已经表现出优异的催化活性和高的对映选择活性.  相似文献   
3.
Two novel chiral BINOL derivatives with bis(benzylamine) groups at the 3,3- positions have been synthesized through the condensation reaction between 2,2'-bis(methoxy- methyleneoxy)-1,1'-binaphthyl-3,3'-dicarboxylic acid and benzylamine or N-phenyl benzylamine in the presence of triethylamine. Suitable single crystal of (R)-N,N'-dibenzyl-2,2'-dihydroxy-1, 1'-binaphthly-3,3'-diformamide (R)-3 for X-ray diffraction was obtained by recrystallization at room temperature from the mixture solvents. Crystallographic data of (R)-3: C40H36N2O6, Mr = 640.71, monoclinic, space group P21, a = 6.746(3), b = 21.883(9), c = 11.723(5) , β = 104.605(7)°, Z = 2, V = 1674.7(12) 3, Dc = 1.271 g/cm3, F(000) = 676, R = 0.0729, wR = 0.1687 and μ(MoKα) = 0.086 mm-1. Two chiral BINOL ligands were found to be effective in the enantioselective addition of diethylzinc to aldehydes and much different enantioselectivity was observed both in the presence and absence of Ti(OiPr)4. In the former case, (R)-3 showed moderate enantioselectivity, which was lower than that of (R)-BINOL's; and in the latter case, (R)-4 gave the highest enan- tioselectivity up to 93.3% ee.*  相似文献   
4.
薛允宁  刘国华  薛思佳 《应用化学》2006,23(11):1200-1203
二氯苯氧丙酸;嘧啶;酰胺;合成;除草活性  相似文献   
5.
The title compound N-(7-chloro-5-ethoxy-2H-[1,2,4]thiadiazolo[2,3-a]pyrimidin- 2-ylidene)- 2-(2,4-dichlorophenoxy)propanamide 3 has been synthesized through using bromine as cyclic reagent in 63% isolated yield. Suitable single crystals for X-ray diffraction were obtained by recrystallization from the mixture solvents at room temperature. Crystallographic data of 3: C16H13- Cl3O3S, Mr = 447.71, triclinic, space group P, a = 8.7461(8), b = 9.9560(10), c = 11.8572(11) , α = 94.341(2), β = 94.683(2), γ = 112.929(2)o, Z = 2, V = 941.21(15) 3, Dc = 1.580 g/cm3, F(000) = 456, R = 0.0794, wR = 0.2056 and μ(MoKα) = 0.623 mm-1. The title compound 3 was found to be effective in herbicidal activity.  相似文献   
6.
报道了一个4,6-二甲氧基嘧啶取代的硫脲的分子结构和二维构筑体系.在这个分子中,通过强分子内氢键锁硫脲的3个主要片段促使分子呈现近平面结构;不同类型的弱分子间C-H—S和C-H—O氢键导致分子形成不同类型的二聚单元;这些二聚单元结合分子间的偶极-偶极促使分子呈现不同类型的席状体系;另外,π-π堆积和氯/氯间紧密相互作用导致嘧啶取代的硫脲分子呈现高度有序的交错层的自聚集体系.  相似文献   
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