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1.
用二丁基氧化锡与苯磺酸、甲磺酸反应制备了两种新的有机锡化合物——二丁基锡(Ⅳ)磺酸酯.以二丁基锡(Ⅳ)磺酸酯作催化剂,合成了一系列缩醛(酮),并通过正交实验,优化了有机锡催化缩醛(酮)合成反应的反应条件.实验表明该催化反应产率高,反应时间短,催化剂用量少且能回收再利用.  相似文献   

2.
二丁基锡磺酸酯催化酯交换合成碳酸二苯酯   总被引:1,自引:1,他引:1  
研究了不同类型的酸催化剂对碳酸二甲酯与苯酚酯交换合成碳酸二苯酯的影响. 实验结果表明, 碳酸二甲酯与苯酚的酯交换反应是软碱(酚氧)亲硬酸(羰基碳)的反应; 硬Lewis酸比软Lewis酸、交界Lewis酸和Brönsted酸有更高的酯交换选择性. 将不同的磺基引入n-Bu2SnO分子中, 制得一系列硬Lewis酸催化剂[n-Bu2Sn(OH)OS(O)2R(H2O)]2[R=p-NH2C6H4(Ⅰ), p-CH3C6H4(Ⅱ), C6H5(Ⅲ), p-ClC6H4(Ⅳ), Me(Ⅴ), CF3(Ⅵ)]. 在酯交换反应中, 由于磺基的强吸电子效应增强了[n-Bu2Sn(OH)OS(O)2R(H2O)]2中Sn的Lewis酸性, 其催化活性比n-Bu2SnO的高, 而且磺基上取代基的吸电子效应越强, 催化剂中Sn的Lewis酸性越强, 催化活性越高, 但取代基的吸电子效应过强会降低其对酯交换反应的选择性.  相似文献   

3.
HMAS-5分子筛催化合成缩醛(酮)   总被引:4,自引:0,他引:4  
研究了HMAS_5分子筛催化乙二醇与环己酮、丁酮、丙酮、丙醛、丁醛、异丁醛、戊醛、异戊醛、正己醛、正辛醛、苯甲醛等醛(酮)的缩合反应。考察了反应时间、醛(酮)与醇的配比、HMAS_5分子筛用量等因素对醛(酮)与醇缩合反应的影响。结果表明,HMAS_5分子筛对醛(酮)与醇的缩合反应有较好的催化性能,选择性一般在98%以上,转化率也一般在90%以上。  相似文献   

4.
脱铝超稳Y沸催化合成缩醛(酮)   总被引:6,自引:0,他引:6  
张敏  蒋小平  王琼 《应用化学》2001,18(6):484-486
缩酮;沸石;脱铝超稳Y沸催化合成缩醛(酮)  相似文献   

5.
以离子液体1-十六烷基-3-甲基溴代咪唑为模板剂合成了Al-MSU-S-Y介孔分子筛,利用XRD、N2吸附-脱附对其进行结构表征,结果表明该方法合成的样品具有较大的孔径、孔容以及比表面积,而且孔径分布较窄.研究了Al-MSU-S-Y对乙二醇与环己酮、丁酮、丙酮、丙醛、丁醛、异丁醛、戊醛、异戊醛、正己醛、正辛醛、苯甲醛等十余种醛(酮)的缩合反应的催化性能,结果表明Al-MSU-S-Y介孔分子筛对醛(酮)与醇的缩合反应有较好的催化性能.  相似文献   

6.
磷钨酸镧催化合成缩醛(酮)的研究   总被引:2,自引:0,他引:2  
以磷钨酸镧为催化剂催化合成了苯甲醛乙二醇缩醛、苯甲醛1,2-丙二醇缩醛及环己酮乙二醇缩酮.较系统研究了反应物料配比、催化剂用量、反应时间、催化剂重复使用性能等因素对反应的影响.结果表明:在醛(酮)/二元醇(乙二醇、1,2-丙二醇)=1.0:1.5(mol/mol),催化剂用量为反应物料总质量的1.0%,环己烷为带水剂,在反应温度86~96℃条件下,反应时间2.0h,苯甲醛乙二醇缩醛收率为78.5%,苯甲醛1,2-丙二醇缩醛收率为76.1%,环己酮乙二醇缩酮收率为79.5%.  相似文献   

7.
在氮气保护下,1-乙炔茚满醇与三苯基氢化锡进行游离基加成反应,获得加成物(Z)-1-[2-(三苯基锡基)乙烯基]-1-茚满醇(1);将加成物(1)与苯酐反应,得到新型邻苯二甲酸单酯有机锡衍生物(2);衍生物(2)分别与二丁基氧化锡和三苯基氧化锡进行脱水反应,分别获得两个新型邻苯二甲酸酯的有机锡衍生物(3)和(4).将加成物(1)与卤素反应后,与锡原子直接相连的苯基被取代,得到一卤代和二卤代物(5~10).通过元素分析、1HNMR和IR等手段对化合物1~10进行了结构表征,确定了该类邻苯二甲酸单酯和邻苯二甲酸酯的有机锡衍生物的结构.并测定了加成物(1)和一溴代物(6)的晶体结构,在加成物(1)中,由于分子内存在较弱的O→Sn[0.2778(8)nm]配位作用,锡原子呈扭曲三角双锥构型.在一溴代物(6)分子中,存在分子内O→Sn[0.2364(2)nm]配位键,锡原子呈扭曲的三角双锥构型.该系列化合物分子内的O→Sn配位能力和Lewis酸性强弱的顺序为:二卤化物>一卤化物>加成物;氯代物>溴代物>碘代物>加成物.  相似文献   

8.
在全氟溶剂中全氟辛基磺酸稀土金属盐催化合成缩醛   总被引:1,自引:0,他引:1  
易文斌  蔡春 《应用化学》2006,23(11):1295-0
氟两相催化;全氟辛基磺酸稀土金属盐;全氟溶剂;缩醛  相似文献   

9.
高分子催化剂聚氯乙烯—三氯化铁催化合成缩醛(酮)   总被引:23,自引:0,他引:23  
本文首次将高分子催化剂聚氯乙烯—三氯化铁应用于缩醛和缩酮的合成中,乙二醇或1,2—丙二醇与醛或酮的羰基作用生成缩醛或缩酮。当0.2mol醛或酮与0.3mol醇的混合物在0.5g催化剂作用下,用环已烷为溶剂,回流反应50分钟,其收率为78—91%。  相似文献   

10.
季戊四醇双缩醛、双缩酮化合物在工业和有机合成中应用广泛。工业上常作为增塑剂、抗氧剂、杀虫剂和表面活性剂的消泡剂,在有机合成中用来合成有生理活性的物质和作为醛、酮的保护基团。季戊四醇双缩醛、酮的合成通常在酸性条件下进行,已报道的催化剂有质子酸:如盐酸[1]、硫酸[  相似文献   

11.
Diorganotin(IV) and diorganosilicon(IV) derivatives of the types R2MCl(TSCZ) and R2M(TSCZ)2 (where TSCZ is the anion of a thiosemicarbazone ligand, R=Ph or Me and M=Sn or Si) have been synthesized and characterized by elemental analyses, molecular weight determinations and conductivity measurements. The mode of bonding has been established on the basis of IR and 1H, 13C 29Si and 119Sn NMR spectroscopic studies. Some of the representative complexes have also been evaluated for their antimicrobial effects on different species of pathogenic fungi and bacteria in vivoas well as in vitro.The results of these investigations are reported. © 1998 John Wiley & Sons, Ltd.  相似文献   

12.
Abstract

A series of new organotin(IV) dithiocarbamate compounds of type RnSn (S2CNR′R″)4-n (n = 2, 3; R = dimethyl, dibutyl, diphenyl, triphenyl and tert-butyl; R′ = methyl, ethyl, benzyl; R″ = isopropyl, ethyl, ethanol) have been successfully synthesized. Elemental analysis showed that the percentage of the elements conformed to the general formula of these compounds. The important peaks of the infrared spectra for the stretching mode ν(C?N), ν(C?S), and v(Sn-S) for the compounds were observed in the area of 1440–1480 cm?1, 940–1000 cm?1, and 340–90 cm?1, respectively. The 13C NMR spectra showed the most important peak for N13CS2 chemical shifts were observed in the range 190–210 ppm. X-ray single crystal studies for several structures of these compounds showed that the chelating mode of the dithiocarbamate groups to the central tin atoms were either bidentate or anisobidentate.

GRAPHICAL ABSTRACT  相似文献   

13.
Abstract

The reaction of Me2SnCl2 with dithizone or thiosemicarbazide produced two novel di-organotin derivatives in good yields, which were characterized by X-ray diffraction. The crystal structures show that the compounds present a distorted pentacoordinated tin(IV) metal center. The antimicrobial activity of the new compounds was studied against Gram-negative (Escherichia coli, Klebsiella pneumonia, Salmonella enteritidis) and Gram-positive (Staphylococcus aureus) bacteria, and the yeast Saccharomyces cerevisiae. It was observed that the coordination of tin metal has a pronounced effect on the microbial activities of the ligands. All the tin complexes have shown higher antimicrobial effect than the free ligands.

GRAPHICAL ABSTRACT  相似文献   

14.
The diorganotin(IV) and triorganotin(IV) derivatives R2SnA (R = Me, n-Pr, n-Bu, n-Oct) and (R3Sn)2A [R = Me, Ph, cyclohexyl (Cyh); A = an anion of diphenic acid] have been prepared and characterized by elemental analysis, IR, 1H and 13C NMR spectroscopies. Tetrahedral tin forms a part of a diphenate cyclic ring in the diorganotin complexes with unidentate carboxylates, which have further been used for the synthesis of cyclic acid anhydrides. The soluble dinuclear triorganotin complexes (Me, Ph) possess symmetrically bonded carboxylates while the less soluble compound (Cyh3Sn)2A has two asymmetrically bonded carboxylates. All have a trigonal bipyramidal structure with R3Sn units remote from each other.  相似文献   

15.
A comprehensive review on antimicrobial activity of organotin(IV) compounds is presented. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

16.
The crystal lattice of the title compound comprises isolated molecules. The coordination polyhedron is a slightly distorted tetrahedron with C–Sn–C bond angles ranging from 106.62(17)° to 113.9(3)°. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

17.
Four new tin(IV)/organotin(IV) complexes, [SnCl3(BPCT)] (2), [MeSnCl2(BPCT)] (3), [Me2SnCl(BPCT)] (4), and [Ph2SnCl(BPCT)] (5), have been synthesized by the direct reaction of 2-benzoylpyridine-N(4)-cyclohexylthiosemicarbazone [HBPCT, (1)] and stannic chloride/organotin(IV) chloride(s) in absolute methanol under purified nitrogen. HBPCT and its tin(IV)/organotin(IV) complexes (25) were characterized by CHN analyses, molar conductivity, UV-Vis, FT-IR, and 1H NMR spectral studies. In all the complexes, tin(IV) was coordinated via pyridine-N, azomethine-N, and thiolato-S from 1. The molecular structure of 2 has been determined by X-ray single-crystal diffraction analysis. Complex 2 is a monomer and the central tin(IV) is six-coordinate in a distorted octahedral geometry. The crystal system of 2 is monoclinic with space group P121/n1 and the unit cell dimensions are a?=?8.3564(3)?Å, b?=?23.1321(8)?Å, c?=?11.9984(4)?Å.  相似文献   

18.
The six organotin complexes dibutyltin(IV) bis(heteroaromatic carboxylate) were synthesized by the reaction of (n‐Bu)2SnO with heteroaromatic carboxylic acid in 1:2 molar ratio. These complexes have been characterized by elemental analysis, IR, 1H, 13C and 119Sn NMR. The crystal structure of dibutyltin(IV) bis(2‐thiazolylcarboxylate) was determined by X‐ray single crystal diffraction. This compound is a weakly bridged dimer through weak interaction Sn···O between molecules. The tin atoms took six‐coordinate skew‐trapezoidal bipyramidal geometry. The crystal of complex 3 belongs to monoclinic symmetry with space group P21/c, a=1.863(2) nm, b=2.220(3) nm, c=1.0395(10) nm, β=90.275(16)°, Z=8, V=4.292(8) nm3, Dc=1.514 Mg/m3, μ=1.406 mm‐1, F(000)=1968, S=0.999, R=0.0549, wR=0.1011.  相似文献   

19.
四烃基二锡氧烷的催化缩醛化性能研究   总被引:9,自引:0,他引:9  
兰支利  吕妍  李靖  谢庆兰 《催化学报》2001,22(5):423-426
 合成了一系列含不同烃基和官能团的二锡氧烷,并考察了其对巴豆醛与乙二醇缩合反应的催化作用.结果表明,四烃基二锡氧烷是高效的缩醛化反应催化剂,烃基对催化活性的影响主要归因于其空间位阻效应.二锡氧烷结构中内外锡原子上的烃基都对反应有影响,直链烃基催化剂的活性高于环烃基催化剂,碳数少的直链烃基催化剂的活性高于碳数多的.二锡氧烷上桥联基团的活性顺序为NCS>CH3O>Cl>CH3COO.这与其同乙二醇取代反应的难易程度相关联.提出了巴豆醛与乙二醇的缩合反应机理图式.  相似文献   

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