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1.
合成了一系列(1,1'-联苯)-2-二(1-金刚烷基)磷配体,并制备出8种相应的Au(Ⅰ)配合物.以甲醇为溶剂,在6-十二炔水合反应中考察了8种Au(Ⅰ)配合物的催化性能,结果表明,以含有3'-(吡咯-1-羰基)官能团的Au(Ⅰ)配合物为催化剂时,其用量仅需炔烃用量的0.1%~0.3%(摩尔分数),室温下即可高效地催化炔烃进行水合反应.  相似文献   

2.
研究了13种钴(Ⅱ)-氨基酸配合物的可逆氧合性能和催化性能之间的关系, 通过配合物活化分子氧(O2)氧化环己烯考察其催化性能. 结果表明, 13种钴(Ⅱ)-氨基酸配合物均具有不同程度的可逆氧合性能和催化活性. 配合物完成一个可逆吸氧周期的用时越短, 其可逆氧合性能越好, 催化性能越差; 相反, 吸氧周期长及可逆氧合性能差的配合物其催化性能却更好. 另外, 在对配合物不同配比的研究中发现, Co(Ⅱ)与氨基酸的摩尔比为1:3(或1:2)饱和配位时, 可逆吸氧性能较好, 但其催化性能较差, 环己烯转化率较低; 在1:1型配位不饱和时, 吸氧的可逆性较差, 但催化性能优良, 环己烯的转化率可达82.5%. 结合结构分析和理论计算的结果可知, 不同钴(Ⅱ)-氨基酸配合物的氧合可逆性和催化性能的差异, 主要归因于氨基酸配体的残基与Co(Ⅱ)的结合能力的不同. 氨基酸配体的残基与Co(Ⅱ)的结合能力越好, 越有利于配合物由高自旋态向低自旋态转化, 并与O2可逆结合, 不利于烯烃基的取代, 配合物表现出较差的催化性能, 反之亦然.  相似文献   

3.
在甲醇溶液中, 还原希夫碱HL[N-(2-吡啶甲基)-L-丝氨酸]与CuCl2·2H2O以摩尔比1∶1反应, 得到1个新的中性单核铜配合物[CuLCl(H2O)](Ⅰ). 通过X射线单晶衍射、 元素分析、 红外光谱、 电喷雾质谱和粉末X射线衍射分析等对其进行了表征. 晶体结构分析表明, 在该配合物中还原希夫碱以三齿双螯合环配位到中心铜离子, 同时氯离子和溶剂水分子也参与配位, 形成1个具有四方锥构型的五配位铜(Ⅱ)配合物, 该配合物通过分子间弱相互作用连接成二维超分子结构. 生物活性测试结果表明, 配合物Ⅰ能有效抑制蛋白酪氨酸磷酸酶1B(PTP1B)和T细胞蛋白酪氨酸磷酸酶(TCPTP), IC50值分别为0.32和0.45 μmol/L.  相似文献   

4.
金催化的吲哚与末端炔烃的分子间烷基化反应   总被引:1,自引:0,他引:1  
尝试了用金(Au)催化吲哚和炔烃的Friedel-Crafts烷基化反应, 具体探讨了金(I)配合物催化吲哚与末端炔烃的烷基化反应的条件, 并制备了一系列尚未见文献报道的双取代β-吲哚烷基化衍生物. 产物的结构经1H NMR, 13C NMR, MS和元素分析确证. 并对其反应机理可能性进行了推测.  相似文献   

5.
合成了四种新型茚基膦金配合物,其结构经1H NMR,31P NMR和元素分析表征,同时,两种配合物的结构通过X射线单晶衍射确证.化合物2能高效地催化炔烃水合反应,该催化反应具有反应条件温和、催化剂用量少、原子经济性好、对环境友好等优点.  相似文献   

6.
朱诗敏  黄鑫  韩勰  刘思敏 《化学学报》2022,80(8):1066-1070
由于过渡金属配合物具有独特的光物理化学性质而被广泛研究. 其中Pt(Ⅱ)配合物发生组装时会因Pt(Ⅱ)-Pt(Ⅱ)之间的距离不同而显示不同的荧光特性, 而主客体相互作用可以影响发光小分子的排列及组装. 为进一步探究主客体相互作用对Pt(Ⅱ)配合物发光性能的影响, 设计合成了不同取代的N^C^N型Pt(Ⅱ)配合物, 研究了大环主体葫芦[10]脲(CB[10])对这类配合物的识别作用及包合物的光谱性质. 核磁共振氢谱和质谱证明CB[10]可与配合物以1∶2的比例结合. 紫外-可见吸收光谱和荧光发射光谱分析表明主客体作用对该类金属配合物光谱性质有较大影响, 所形成的主客体包合物的磷光寿命及量子产率都有不同程度的变化. 研究结果表明, CB[10]可通过包结两个Pt(Ⅱ)配合物分子, 拉近铂原子之间的距离, 增强该类配合物在水相中的Pt(II)…Pt(II)相互作用和π-π相互作用, 实现水相中的长寿命磷光发射. 同时, 主客体作用对这类金属配合物的力致变色性质也有一定的影响.  相似文献   

7.
硫酸高铈催化炔烃的水合反应研究   总被引:1,自引:0,他引:1  
刘文杰  李金恒 《有机化学》2006,26(8):1073-1078
炔烃经水合反应生成酮是有机合成中最重要和最基本的进行官能团转换的方法之一. 我们提供了一种价廉且具有高选择性的硫酸高铈催化炔烃水合方法. 实验结果表明: 在硫酸高铈(0.1 mmol)、浓硫酸(0.06 mL)、水(0.02 mL)和苯(5 mL)且反应温度为70 ℃的反应条件下, 炔烃(1 mmol)可以顺利发生水合反应生成酮.  相似文献   

8.
选择氧合性能良好的组氨酸(His)-Co(Ⅱ)作为研究对象, 分别掩蔽—NH2、 取代—O-和去除—COO-, 得到短肽、 伪肽和多胺等类组氨酸结构. 采用UV-Vis光谱法研究了α-氨基酸中的3个官能团对其Co(Ⅱ)配合物氧合性能的影响. 对比研究表明: α-氨基酸中—NH2对其Co(Ⅱ)配合物的吸氧性具有决定作用; —COO-对其Co(Ⅱ)配合物氧合作用的可逆性起关键作用; 而—O-对其Co(Ⅱ)配合物的吸氧性影响不大. 在前期研究结果的基础上, 对α-氨基酸-Co(Ⅱ)配合物可逆吸收和释放O2的机理进行了探讨.  相似文献   

9.
研究了Fe(Ⅲ)催化氯代炔烃水化生成α-氯代甲基酮化合物的反应, 考察了催化剂的种类、 酸的种类、 反应温度以及溶剂对反应的影响.结果表明, 采用FeCl3·6H2O(摩尔分数5%)和甲基磺酸(摩尔分数20%), 在1,2-二氯乙烷溶剂中, 氯代炔烃于80 ℃进行水化反应3 h, 可以高产率得到α-氯代甲基酮产物. 所得化合物的结构采用IR, 1H NMR, 13C NMR及MS等方法进行了表征. 该水化反应合成方法简单、 条件温和且收率良好, 为合成α-氯代甲基酮提供了一种简便途径.  相似文献   

10.
本文合成了N,N'-双(2'-羟基苯乙酮)缩乙二胺、N,N'-双(2'-羟基苯乙酮)缩1,2-丙二胺、N,N'-双(2'-羟基苯乙酮)缩1,3-丙二胺和N,N'-双(2'-羟基苯乙酮)缩邻苯二胺四种Schiff配体以及它们的锰(Ⅲ)配合物1,2,3和4.并考察了这四种锰(Ⅲ)配合物作为催化剂,催化以NaOCl为氧源环氧化苯乙烯和环己烯的反应的性能.同对考察了反应温度、助配体、NaOCl的浓度以及pH值对催化环氧化反应的影响.  相似文献   

11.
采用表面活性剂自组装、有机金属硅烷与苯基硅烷共聚法制备了有机金属Au(I)嵌于介孔材料孔壁的非均相催化剂Au(I)-PPh2-PMO(Ph).结果表明,Au(I)-PPh2-PMO(Ph)催化剂的活性位分散均匀,孔道不易堵塞,对反应物的扩散与传质影响较小,其催化活性不仅明显高于后嫁接法制得的Au(I)-PPh2-PMO(Ph)-G和均相Au(PPh3)Cl催化剂,且可以重复使用,显示出较好的应用前景.  相似文献   

12.
In this study, N-heterocyclic carbene–Au(I) complex, chloro[1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene]gold (I), was successfully encapsulated within mesopores of a magnetic core/shell (γ-Fe2O3@SiO2) silica gel through post-pore-size reduction by silylation reactions The post-reduction of the pore size not only minimizes the catalyst leaching during the alkyne hydration reactions but also eliminates any need for covalent modification of the catalyst or support surface. The resulting catalyst exhibits high activity in hydration reactions of various alkynes even under low catalytic loadings. The catalyst can be easily recycled from the reaction mixture using a magnet and can be reused in alkyne hydration reactions up to six times with only 52. wt% Au leaching.  相似文献   

13.
有机金催化胺氧化羰化制氨基甲酸酯   总被引:8,自引:1,他引:7  
自Haruta等报道高分散担载金催化剂对CO有良好的低温水除活性以来,金催化剂的研究开发开始受到关注,各种提载型金催化剂在选择氧化、氮氧化物消除、选择加氢、甲烷完全氧化以及均相有机金配合物催化剂在醇醛缩合、烯烃羰化、锡烷的偶联等反应中均取得了相当好的效果,但与Pt和Pd等贵金属相比,金作为具有潜在多种催化能力的催化材料了解尚少。现在工业上主要使用胺类化合物与剧毒的光气反应制取异氰酸酯,该反应造成设备腐蚀和环境污染,因此用胺类化合物氧化羰化或硝基化合物的还原羰化合成氨基甲酸酯,然后热裂解制取相应的异氰酸酯得到广泛研究,过去主要以含氮配体配位的钯催化剂为代表的贵金属为催化剂催化羰化合成氨基甲酸酯,以有机金配合物作为含氮化合物羰化催化剂的研究则未见报道,本文首次将有机金配合物作为胺类化合物氧化羰化制取氨基甲酸酯的催化剂,取得了与钯催化剂相当的催化效果,反应如下:R(NH2)n CO O2 R^1OH[Au(PPh3)x]yZ/→/PPh3R(NHCO2R^1)n H2O R=Ar-,RCH2-;R^1=CH3-,CH3CH2-;n=1 or 2,x=1 or 2,y=1 or 2;Z=cl,NO3,S。  相似文献   

14.
The use of [(IPr)AuOH] as versatile, air- and moisture-stable pre-catalyst permits the in situ generation of the cationic gold(I) species [(IPr)Au]X after reaction with a Brønsted acid. This catalytic system presents as a main advantage the lack of use of a silver salt activator or co-catalyst which is often air-, light- and moisture-sensitive. A general gold(I)-catalyzed procedure using this in situ activation at very low catalyst loading is reported for the hydration of a broad range of internal and terminal alkynes.  相似文献   

15.
In this work, two monomeric magnesium alkyl complexes ( 1 and 2 ) were prepared using bis(phosphino)carbazole framework and among them 1 has been used as a catalyst for hydroboration of alkenes and alkynes with pinacolborane (HBpin). A broad variety of aromatic and aliphatic alkenes and alkynes were efficiently reduced. Anti-Markovnikov regioselective hydroboration of alkenes and alkynes was achieved, which was confirmed by deuterium-labelling experiments. The work represents the first example of the use of magnesium in homogeneous catalytic hydroboration of alkene with broad substrate scope. Experimental mechanistic investigations and DFT calculations provided insights into the reaction mechanism. Finally, the hydroboration protocol was extended to terpenes.  相似文献   

16.
The catalytic activity of [CpRu(L)(2)(MeCN)]PF(6) (L = 2-diphenylphosphinopyridine with bulky groups at C-6) for anti-Markovnikov hydration of terminal alkynes to aldehydes is retained when one heterocyclic ligand L is replaced by L' = PPh(3). Equal amounts of CpRuCl(PPh(3))(2) (1) and phosphane L in acetone solution equilibrate to a mixture of 1, CpRuCl(L)(PPh(3)) (2), and CpRuCl(L)(2) (3), which acts as highly active in situ catalyst for preparative anti-Markovnikov hydration of alkynes in water-rich media (2 mol % [Ru], 60 °C, 3-18 h in 4:1 (v/v) acetone/water). Reactions were completed in <15 min at 160 °C.  相似文献   

17.
The gold nanoparticles with core diameter of 3.9-4.7 nm were stabilized with octanethiolate and dipyridylphosphinicamido undecanethiolate. Without varying the size of central Au cores, palladium complexes were immobilized onto these Au nanoparticles through chelation to the surface-bound dipyridyls. Hybrid catalysts of this type were dissolvable and precipitable, and their structures and reactions were investigated by solution nuclear magnetic resonance (NMR) spectroscopy with a resolution typically attained for soluble systems. These surface-bound Pd(II) complexes were highly effective catalysts for [2+2+2] alkyne cyclotrimerization reactions to give highly congested benzene rings with fairly good selectivity. The catalytic reactivity of these interphase catalysts was even higher than that of their unbound counterparts. In addition, they can be easily separated and quantitatively recovered by simple filtration. The recovered catalysts can be effectively recycled many times and their electron microscopy images and NMR spectra showed negligible difference from those of freshly prepared. The complete transformation by Au-bound Pd(II) catalyst with a loading of 4 mol % can be achieved within 1 h for most alkynes. The same catalysis can be further accelerated in ionic liquid under microwave conditions to give nearly 100% of cyclotrimerized products in minutes.  相似文献   

18.
The Sn–W mixed oxide prepared by calcination of the Sn–W mixed hydroxide precursor with a Sn/W molar ratio of 2:1 at 800 °C (SnW2‐800) acts as an efficient heterogeneous catalyst for the hydration of alkynes. Structurally diverse terminal and internal alkynes, including aromatic, aliphatic, and double‐bond‐containing ones, can be converted into the corresponding ketones in moderate to high yields. The catalytic activity of SnW2‐800 is much higher than those of previously reported heterogeneous catalysts and commonly utilized acid catalysts. The observed catalysis was truly heterogeneous, and the retrieved catalyst can be reused at least three times with retention of its high catalytic performance. The reaction rate for the SnW2‐800‐catalyzed hydration was decreased by addition of 2,6‐lutidine and the hydration hardly proceeded in the presence of an equimolar amount of this compound with respect to that of the Brønsted acid sites in SnW2‐800. Therefore, the present hydration is mainly promoted by the Brønsted acid sites in SnW2‐800.  相似文献   

19.
An operationally simple approach for the preparation of a new class of bifunctional Au nanoparticle-acid catalysts has been developed. In situ reduction of Au(3+) with HS-functionalized periodic mesoporous organosilicas (PMOs) creates robust, fine Au nanoparticles and concomitantly produces a sulfonic acid moiety strongly bonded to PMOs. Characterizations of the nanostructures reveal that Au nanoparticles are formed with uniformed, narrow size distribution around 1-2 nm, which is very critical for essential catalytic activities. Moreover, the Au nanoparticles are mainly attached onto the pore surface rather than onto the outer surface with ordered mesoporous channels, allowing for maximal exposure to reaction substrates while minimizing Au nanoparticle leaching. Their higher S(BET), V(P), and D(P) than either the Au-HS-PMO(Et) or the Au/SO(3)H-PMO(Et) render the catalyst with comparably even higher catalytic efficiency than its homogeneous counterparts. Furthermore, the unique amphiphilic compartment of the Au-HS/SO(3)H-PMO(Et) nanostructures enables organic reactions to proceed efficiently in a pure aqueous solution without using any organic solvents or even without water. As demonstrated experimentally, remarkably, the unique bifunctional Au-HS/SO(3)H-PMO(Et) catalyst displays higher efficiencies in promoting water-medium alkyne hydration, intramolecular hydroamination, styrene oxidation, and three-component coupling reactions and even the solvent-free alkyne hydration process than its homogeneous catalysts. The robust catalyst can be easily recycled and used repetitively at least 10 times without loss of catalytic efficiency. These features render the catalyst particularly attractive in the practice of organic synthesis in an environmentally friendly manner.  相似文献   

20.
Zhou CY  Chan PW  Che CM 《Organic letters》2006,8(2):325-328
[reaction: see text] Gold(III) porphyrin-catalyzed cycloisomerization of allenones gave the corresponding furans in good to excellent yields (up to 98%) and with quantitative substrate conversions. By recovering the Au(III) catalyst, a recyclable catalytic system is developed with over 8300 product turnovers attained for the cycloisomerization of 1-phenyl-buta-2,3-dien-1-one. The versatility of the gold(III) porphyrin catalyst was exemplified by its application to the hydroamination and hydration of phenylacetylene in 73% and 87% yield, respectively.  相似文献   

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