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1.
四苯氧基酞菁镁、锰、铝和锌的合成和性质   总被引:2,自引:0,他引:2       下载免费PDF全文
合成了新的酞菁配合物4,4,4,4-四苯氧基酞菁镁[TPhOPcMg(Ⅱ)],锰[TPhOPcMn(Ⅱ)Ac],铝[TPhOPcAl(Ⅲ)Cl],锌[TPhOPcZn(Ⅱ)]测定了它们的IR,UV-Vis光谱,在DMF中的氧化还原半波电势(E1/2),电子转移速度常数,在乙腈中的荧光性质及锰的配合物在不同电位下的光谱变化情况。  相似文献   

2.
利用多核Nd-Al双金属配合物可单独引发双烯聚合的特点,考察了烷基铝种类对丁二烯加聚过程的影响,并与一般混合稀土催化体系进行了比较,烷基铝对活性体催化活性的影响与其用量有关,低n(Al)n(Nd)值时,活性次序为:AlMe3,AlEt3,HAlB2〉Al(C8H17)3〉AlBu3;高n(Al)/n(Nd)值时,欠序相反,AlMe3AleT3,HAlBu2〈Al(C8h1703〈AlBu3,烷基铝  相似文献   

3.
利用多核Nd-Al双金属配合物可单独引发双烯烃聚合的特点,考察了烷基铝种类对丁二烯加聚过程的影响,并与一般混合稀土催化体系进行了比较.烷基铝对活性体催化活性的影响与其用量有关,低n(Al)/n(Nd)值时,活性次序为:AlMe3,AlEt3,HAlBui2>Al(C8H17)3>AlBui3;高n(Al)/n(Nd)值时,活性次序相反:AlMe3,AlEt3,HAlBui2<Al(C8H17)3<AlBui3.烷基铝链转移作用强弱次序为:HAlBui2≥AlEt3>AlBui3>AlMe3>Al(C8H17)3.根据聚丁二烯微观结构与其分子量的关系,可将烷基铝对聚丁二烯顺式含量的影响分为3类:(1)AlEt3和Al(C8H17)3;(2)HAl-Bui2和AlBui3;(3)AlMe3.所得结果有助于对稀土催化定向聚合过程的深入了解.  相似文献   

4.
单茂钛化合物/MAO/AlR_3均相催化体系合成sPS与aPP研究   总被引:4,自引:1,他引:4  
先考察部分水解三甲基铝(TMA)制备固体改性甲基铝氧烷(m MAO)时,反应物H2O和TMA的摩尔比对固体产物m MAO中TMA含量的影响;然后考察不同的钛化合物特别是茂钛化合物(LnTiXn′,n=1,2,n′=2,3)和m MAO组成的均相催化体系分别进行苯乙烯间规聚合和丙烯无规聚合的效果作比较.在此基础上分析以茂基三正丙氧基钛[CpTi(OPrn)3]为主催化剂,不同TMA含量的m MAO为助催化剂,及外加各种烷基铝(AlR3)所组成的催化体系中钛的氧化数,同时对苯乙烯间规聚合和丙烯无规聚合进行比较研究,从中发现活性中心钛的氧化数以Ti(Ⅲ)为主时有利于苯乙烯间规聚合,不利于丙烯无规聚合;而氧化数以Ti(Ⅳ)为主时则对丙烯无规聚合有利.苯乙烯间规聚合时,外加烷基铝可节省MAO用量.  相似文献   

5.
在溴化十六烷基三甲胺(CTMAB)存在下,PH6,0的HAc-NaAc缓冲介质中,铝与新试剂3,5-二溴-4-偶氮8-羟基喹啉苯基荧光酮形成红色三元胶束配合物,最大吸收波长位于564nm,表观摩尔吸光系数ε为1.35×10^5.mol^-1.cm^-1,铝浓度在0~5μg/25mL范围内符合比耳定律,拟定的方法用于铝铁黄铜中微量铝的测定,结果满意。  相似文献   

6.
邓凡政  石影 《分析化学》1997,25(2):215-218
研究了在聚乙二醇-硫酸铵-铝试剂体系中Fe(Ⅲ),Al(Ⅲ)、Cu(Ⅱ)、CoⅡ)Cd(Ⅱ)Mn(Ⅱ)、Ni(Ⅱ)的萃取分离行为。结果表明,在PH5.0-6.5HAc-NaAc缓冲溶液中,Fe(Ⅲ)、Al(Ⅲ)可被PEG相几乎完全萃取,而Cu(Ⅱ)、Co(Ⅱ)Cd(Ⅱ)Mn(Ⅱ)基本上不被萃取,从而实现了Fe(Ⅱ)与Cu(Ⅱ)Co(Ⅱ)Cd(Ⅱ)Mn(Ⅱ)及Al(Ⅲ)与Fe(Ⅲ)Co(Ⅱ)、Cu(  相似文献   

7.
本文在文[1-4]的基础上,研究了在溴化十六烷基三甲基铵(CTMAB)存在下铝与水杨基萤光酮(SAF)的显色反应。在pH4.9的介质中,配合物的最大吸收峰位于552nm,表观摩尔吸光系数为1.14x10 ̄5L·mol ̄(-1)·cm ̄(-1)。铝与水杨基萤光酮的络合比为1:2。铝量在0-7.0μg/25ml范围内符合比耳定律。该体系是光度法测定铝的灵敏显色反应之一,方法有一定选择性,用于航空润滑油中铝的测定,结果较为满意。  相似文献   

8.
提出了在乙酸钠-乙酸介质中,利用Al-EGTA-PR-CPB四元体系测定铝的新方法。试验表明乙二醇二乙醚二氨基四乙酸(EGTA),铝,邻苯三酚红(PR),溴化十六烷基吡啶(CPB)可迅速反应生成四元蓝色配合物Al·EGTA·PR3·CPB12,可用于痕量铝的测定,ε=1.1×10^5L·mol^-1·cm^-1,RSD为5.8%(n=6)。加标回收率101.7% ̄105.0%,实测水和化学试剂中痕  相似文献   

9.
采用快速混合停流技术,在实际反应条件下,考察了五氟代锰卟啉配合物Mn~Ⅲ(TFPP)C1与两种单氧给体亚碘酰苯PhIO和过氧苯甲酸m-CPBA构建的细胞色素P-450模拟酶体系催化活性物种的生成及催化烯烃环氧化过程.在氧给体PhIO作用下,Mn~Ⅲ(TFPP)C1生成了高价锰氧卟啉配合物和双核μ-氧锰卟啉配合物,具有高的催化环氧化活性和催化剂稳定性.而在氧给体m-CPBA作用下,Mn~Ⅲ(TFPP)C1则生成了一种较稳定物种,以致催化活性较低。  相似文献   

10.
本文将稀土络合物Nd(P204)3,Nd(P507),Nd(naph)3,Nd(acac)3.3H2O与烷基铝组成的二元体系催化剂用于共聚马来酸酐(MAn)与环氧丙烷(PO)获得成功,并采用1H-NMR研究了共聚的优良催化剂,可得到高转化率,高交替度共聚物,共聚物数均分子量Mn和分子量分布分别为2000-3000,1.3-1.7,共聚物中MAn的摩尔含量40%以上。共聚物组成及序列分布与投料比,催  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

14.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

17.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

18.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

19.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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