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1.
《合成通讯》2013,43(24):3863-3870
Bis-glycosyloxy-arenes were prepared in very good yields by reaction of the bis-hydroxy-arene on the appropriate unsaturated glycosyl carbonate at room temperature in the presence of a palladium(0) catalyst.  相似文献   

2.
The palladium(0) catalyzed amination of allylic acetates and carbonates derivatives from terpenic olefins was carried out under mild conditions. The reaction offers a very good method for the preparation of allylic amines and thus to provide a useful entry to new functionalized terpenic olefin products. The mechanism involving a formation of p-allyl-palladium intermediate complex is in good agreement with the results obtained with the optically active substrates, as well as via an analysis of the observed regio-and stereoselectivity.   相似文献   

3.
近年在过渡金属有机化合物的反应性能和催化作用的研究中发现了许多新颖的反应和有价值的有机合成方法.本文将就钯配合物在合成环状化合物,形成碳-碳键和制备醛、酮、羧酸及其衍生物中的一些重要应用作一综述.  相似文献   

4.
有机硅聚合物负载环硫乙烷钯(0)配合物的合成与催化性能   总被引:3,自引:0,他引:3  
4 氧杂 6 ,7 环硫庚基三甲氧基硅烷依次与气相法二氧化硅、氯化钯作用,再用水合肼还原,合成了二氧化硅固载的聚4 氧杂 6 ,7 环硫庚基硅氧烷钯(0) 配合物,研究了其催化共轭烯烃的 Heck 芳基化性能  相似文献   

5.
新显色剂邻磺酸基苯偶氮若丹宁合成及与钯的光度法研究   总被引:2,自引:1,他引:2  
报道了新显色剂邻磺酸基苯偶氮若丹宁(o-SBAR)的合成及其与钯显色反应的性能。在2.4mol· L~(-1)磷酸介质中,试剂与钯形成 1: 1的桔红色配合物,在 520nm波长处配合物有最大吸收,表观摩尔吸光系数为6.65×10~4,反应速度快,选择性高,应用于钯碳催化剂中钯的测定,结果满意。  相似文献   

6.
研究了新显色剂2-2-(咪唑偶氮)-5-二乙氨基苯胺(IZAEA)与Pd2+显色反应的条件。试验结果表明,在pHL5. 0的HOAc-NaOAc介质中,试剂与Pd2+形成稳定的紫红色络合构,此络合物不被强酸分解,其它金属离子与试剂形成的有色络合构均被强酸分解。络合物的λmax为564nm,试剂的λmax为476nm,对比度△λ为88nm,Pd2+与试剂的络合比为l2,表观摩尔吸光系数为2.81×104L·mol-1·cm-1,Pdz+浓度在0~0.8mg·L-1范围内遵守比耳定律。所拟方法直接测定催化剂和分子筛中微量钯,结果满意。  相似文献   

7.
在探索 2 氧代 1 ,4 二氧六环应用的实验中 ,我们发现利用 2 氧代 1 ,4 二氧六环与氯化亚砜及一些低碳醇反应 ,可以使 2 氧代 1 ,4 二氧六环发生开环反应 ,生成一类新的有机氯代醚酯类化合物——— 2 ( 2 氯乙氧基 )乙酸酯。其中 ,R分别为甲基、乙基、丙基、异丙基、丁基和仲丁基。该类化合物在酸性、碱性条件下水解 ,可以得到不同的产物。由于 2 氧代 1 ,4 二氧六环可由一缩二乙二醇经催化脱氢得到[1 ] ,而一缩二乙二醇又是工业上制备乙二醇的副产物。因而开展有关 2 ( 2 氯乙氧基 )乙酸酯的合成及性质方面的研究可为一缩二乙二…  相似文献   

8.
壳聚糖钯配位络合物的合成、表征及其催化性能研究   总被引:1,自引:0,他引:1  
用不同方法制备了壳聚糖钯配住络合物,并用FFIR,XPS,XRD和DTA-TG对其进行了表征,结果表明壳聚糖与钯发生配住作用形成了壳聚糖钯配位络合物,研究了该络合物对碘代笨与丙烯酸进行交叉偶联烷基化反应的催化性能,结果表明其具有良好的催化活性。  相似文献   

9.
合成了新试剂 5 磺酸基 [杯 (4)芳烃偶氮 ]氨基喹啉 (SCAQ) ,研究了该试剂与钯 (Ⅱ )显色反应的适宜条件 ,在pH 8.0的缓冲介质中 ,在非离子表面活性剂TritonX 10 0存在下 ,试剂与钯(Ⅱ )生成 1∶1稳定配合物 ,建立了测定钯 (Ⅱ )的光度法新体系 ,体系至少可稳定 6h ,λmax=6 6 0nm ,ε =7.88× 10 4 L·mol- 1·cm- 1,钯 (Ⅱ )浓度在 0~ 30 μg/ 2 5ml范围内服从比耳定律。方法已用于钯催化剂中钯 (Ⅱ )的测定 ,结果与原子吸收光谱法相符 ,RSD为 1.5 %~ 2 .6 %。  相似文献   

10.
Abstract

3-Aryloxymethyl-4-phenyl-5-mercapto-s-triazoles (Ia-c) have been synthesized and reacted with N-chloroacetyl derivatives of aromatic and/or heterocyclic amines to yield 5-(N-aryl/heterocyclyl)-carboxamidomethyl thio-s-triazole derivatives 2a-o and 3a-o respectively. Reaction of Ia-u with ethyl chloroacetate gave the corresponding esters 4a-c which were reacted with hydrazine hydrate to give hydrazides 5a-c. Condensation of 5a-c with aromatic aldehydes gave Schiff s bases 6a-u with on cycloaddition reaction with thioglycolic acid yielded 4-thiazolidinones 7a-g. Some of these compounds were screened in vitro for their antibacterial activities.  相似文献   

11.
The pendant nitrogen atom of the Ph2PPy ligand in the Pd(II)-allyl complexes [PdCl(η3-2-CH3-C3H4)(Ph2PPy)] (1) and [Pd(η3-2-CH3-C3H4)(Ph2PPy)2]BF4 (3) has been protonated with methanesulfonic acid to afford the corresponding pyridinium salts [PdCl(η3-2-CH3-C3H4)(Ph2PPyH)](CH3SO3) (1a) and [Pd(η3-2-CH3-C3H4)(Ph2PPyH)2](CH3SO3)2(BF4) (3a).Protonation strongly influences the 1H and 13C NMR spectral parameters of the allyl moieties of 1a and 3a whose signals resonate at lower fields with respect to the parent species indicating that upon protonation Ph2PPy becomes a weaker σ-donor and a stronger Π-acceptor. The allyl moiety, which in 1 is static, becomes dynamic in 1a, the observed syn-syn and anti-anti exchange being due to deligation of the protonated phosphine from the metal centre. Treatment of complex 3 with diethylamine in the presence of fumaronitrile gives the new Pd(0)-olefin complex [Pd(η2-fumaronitrile)(PPh2Py)2] (4) which has been characterized by elemental analysis and NMR spectroscopy. Low temperature protonation of 4 with methanesulfonic acid leads to the bis-protonated species [Pd(η2-fumaronitrile)(Ph2PPyH)2](CH3SO3)2 (4a) which is stable only at temperatures <0 °C.  相似文献   

12.
阻化动力学光度法测定钯的研究   总被引:1,自引:0,他引:1  
根据Pd(Ⅱ)对V(V)氧化二安替比林对氨基苯基甲烷(DApAM)显色反应的阻化作用,建立了一种测定钯的新方法.阻化反应吸光度A和非阻化反应吸光度A_0的最大吸收波长均为530nm,Pd(Ⅱ)的含量在1~10μg/25ml内与△A(A_0—A)呈线性关系,检出限为5×10~(-8)g.ml~(-?)方法用于钯催化剂中钯的测定,结果满意.  相似文献   

13.
Specific chiral ligands have been designed by Trost et al. to perform enantioselective Pd-catalyzed allylic alkylations. It is shown that the Pd(0) complex formed by addition of the Trost ligand (4) to Pd0(dba)2 is not stable in most solvents (acetone, DMF, CH2Cl2). Indeed, Pd0(dba)(4) leads to the formation of a stable PdII complex 5 (X-ray structure), likely by activation of the two N-H bonds of the ligand by the Pd0 centre. The formation of the PdII complex competes with the reaction of Pd0(4) with (E)-PhCHCH-CH(OAc)-Ph, excluding any investigation of the kinetics of the latter reaction. The ionization steps from intermediate (η2-PhCHCH-CH(OAc)-Ph)Pd0(4) were found to be very slow. The cationic P,P complex [(η3-Ph-CH-CH-CH-Ph)Pd(4)]+, expected to be generated by addition of 2 equiv. of 4 to the precursor [(η3-Ph-CH-CH-CH-Ph)Pd(μ-Cl)]2, in the presence of a chloride scavenger, leads to a complex mixture whereas addition of 1 equiv. of 4 affords a stable bis-cationic PdII complex {[(η3-Ph-CH-CH-CH-Ph)Pd]2(4)]}2+, (X-ray structure) via a P,O complexation of each allyl-Pd moieties. This dissymmetric P,O coordination will favour the enantioselectivity of Pd-catalyzed allylic alkylation of (E)-PhCHCH-CH(OAc)-Ph by the control of the regioselectivity of the nucleophilic attack onto the allylic ligand which is responsible of the enantioselectivity of the overall catalytic reaction.  相似文献   

14.
以 2 ,4 二氨基 6 苯基 1,3,5 三嗪 ,2 ,2′ 二氨基 4 ,4′联噻唑 (DABT) ,苯二甲醛及乙二醛等为原料 ,合成了 6个新型结构的含芳杂环聚席夫碱 (DAPIPA ,DAPTPA ,DAPA ,DAPGPBTGZ ,PBTPZ) ,并制备了 2个Fe2 +配合物 (PBTGZ Fe2 + ,PBTPZ Fe2 + ) .利用FTIR和1 H NMR对聚合物的结构进行了表征 ,通过对其中 3个聚席夫碱的热失重分析 ,表明聚合物具有良好的耐热性能 ,借助多功能材料物理特性测试系统 (PPMS :physicalpropertymeasurementsystem)测定配合物的磁性能 ,测定结果表明这些配合物具有相对较高的磁饱和强度 (σs) ,且有典型的S型磁滞回线 ,表明配合物是有机软铁磁体 .  相似文献   

15.
An efficient and stereoselective synthesis of pyrrolidine-, piperidine-, and azepane-type N-heterocycles is described by the intramolecular Pd(0)-catalysed cyclisation of amino allylic carbonates. The use of chiral ligands gave the corresponding heterocyclic derivatives having er values that were from moderate to good.  相似文献   

16.
于pH9.3~10.6Na_2CO_3-NaHCO_3缓冲介质中,在Triton N-101存在下,Pd(Ⅱ)与2-羟基-3-羧基-5-磺酸基苯基重氮氨基偶氮苯(HCSDAA)形成组成比为1:2的红色配合物,其最大吸收波长为530nm,表观摩尔吸光系数为1.05×10~5,线性范围为0~0.7μg·ml~(-1) .结合丁二酮肟螯合,氯仿萃取,方法用于贵金属二次合金中微量钯的测定,相对标准偏差为2.0%(n=6).加标回收率为93.8%~99.3%.  相似文献   

17.
A cationic palladium complex catalyzed arylative cyclization reaction of N-(2-formylaryl)alkynamides with arylboronic acids was developed. This new process provides an efficient way for the synthesis of functionalized 2-quinolinones in good to excellent yields under mild conditions. Some control experiments were conducted to explain the possible mechanism for the formation of the products.  相似文献   

18.
提出用5 (5 硝基 2 吡啶偶氮) 2,4 二氨基甲苯(5 NO2 PADAT)光度法同时测定铜和钯的新体系。室温下,铜与试剂仅能在pH4.5~6.0范围内定量反应,而钯与试剂于强酸性介质中即可显色完全。基于铜配合物可被EDTA分解而钯配合物不被分解,及铜、钯配合物形成的酸度差异,实现了铜、钯的同时测定。铜浓度在0~0.7μg·ml-1、钯浓度在0~0.9μg·ml-1范围内符合比耳定律,其表观摩尔吸光系数分别为ε519Cu=6.70×104L·mol-1·cm-1,ε592Pd=1.25×105L·mol-1·cm-1。方法已成功用于矿样和电镀活化废液中铜、钯的同时测定。  相似文献   

19.
恶唑酮及其衍生物是合成氨基酸、芳基乙酸及许多天然产物的重要中间体[1] 。一般由马尿酸与芳醛在脱水剂醋酐及催化剂如醋酸钠 [2 ]、碳酸钾[3] 、氯化锌[4 ] 、N-氯乙酰 -苯酰胺 -醋酸钠[5] 、KF-Al2 O3[6 ] 等存在下环化脱水 -缩合而得。但大都反应时间长 ,后处理复杂。1 986年 ,Gedye等人 [7]和 Gignere等人 [8]利用微波辐射有效地加速了有机化学反应 ,从此 ,作为一种新的有机合成方法引起了有机化学工作者的高度重视。本文报道将微波技术用于标题化合物的合成 ,获得了预期的效果。1 实验部分WC-1型熔点测定仪 ,温度计未校正 ;Nicol…  相似文献   

20.
The synthesis of 1-isopropyl-substituted carbazoles by the palladium-catalyzed dealkylative cyclization of N-(2-halophenyl)-2,6-diisopropylanilines is described. The reaction involves intramolecular C-C bond formation, coupled with the cleavage of a C-X bond and a C-C bond, and is proposed to proceed through the formation of a dearomatized intermediate.  相似文献   

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