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1.
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
2.
The chemical selectivity of a novel active manganese compound [Mn2^IVμ-O)3(TMTACN)2] (PF6)2 (1) in catalytic oxidation reactions depended on the structure of substrates and 1 was able to catalyze the oxidation of toluene into benzaldehyde and/or benzoic acid under very mild conditions. The following results were obtained: (1) The selectivity of the oxidation depended on the electronic density of double bonds. Reactivity was absent when strong electron-witherawing groups were conjugated with double bonds. (2) Allylic oxidation reactions mostly take place when double bond is present inside a ring system, whilst epoxiclarion reactions occur when the alkene moiety is part of linear chain. (3) In ring systems, the methylene group was more likely to be oxidized than the methyl group on ailylic position. As expected, the C--H bonds at the bridgeheads were unreactive.The secondary hydroxyl groups are more easily to be oxidized than the primary hydroxyl groups. 相似文献
3.
双齿单Schiff碱钴、锰配合物的合成、表征及催化氧化性能的研究 总被引:15,自引:1,他引:15
合成了单S chiff碱配体水杨醛缩邻甲苯胺(^1L)、5-溴水杨醛缩对氯苯胺(^2L)、5-溴水杨醛缩对甲苯胺(3^L)、水杨醛缩对硝基苯胺(^4L)、水杨醛缩对甲苯胺(^5L)、水杨醛缩对氯苯胺(^6L)及其钴、锰配合物,并用MS、^3HNMR、IR以及元素分析等测试技术予以表征,以钴配合物为催化剂活化分子氧氧化环巳烯,高选择性地得到烯丙位的氧化产物;以锰配合物为催化剂、NaOcl为氧化剂催化苯乙烯的环氧化,主要产物为苯乙烯环氧化物。 相似文献
4.
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。同时考察了反应温度、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
5.
6.
[Co(p—Me—PPA)2(H2O)2]Cl的合成及其催化环己烯氧化反应的研究 总被引:5,自引:0,他引:5
环己烯的选择性氧化是一个较难的课题,原冈是环己烯存在两个活性部位易工发生氧化反应:一是烯两基位的氢易被氧化生成环己烯醇和环己烯酮的产物:二是双键易被氧化成环氧化物、环己酮或C—CXX键断裂生成难成酸等。因此人们一直在努力寻找具有高活性,高选择性的催化剂用以催化环己烯的氧化反应[’*’]。本文合成的K叶卜*卜呷A从比0)。厂1,在0。作氧源下m于催化环己烯氧化反应时呈现出较好的转化率和环己烯酮选择性。1【Co(P-Me-PPA)。(H。0)。」C!的合成采m2一毗咙甲酸和p一甲基本胺作原料合成了【… 相似文献
7.
采用乳化溶剂蒸发的方法制备了负载型催化剂环多胺锰/乙基纤维素微胶囊(MnAcL-EC), 并确认了MnAcL在微胶囊内负载后结构的完整性, 对其进行了形貌结构表征, MnAcL-EC微胶囊负载型催化剂内部呈特殊的多芯结构. 该催化剂在活性蓝(C.I. Reactive Blue 49)的氧化反应中表现出了优异的催化性能. 催化反应后微胶囊粒径增大, 球体表面孔道增多; 元素分析结果显示, 微胶囊内负载的MnAcL在催化反应后几乎没有减少, 表明负载后的MnAcL是在微胶囊内部催化了外界底物分子的氧化反应. 所制备的MnAcL-EC微胶囊具备很好的循环利用性, 可以有效减少催化活性组分的流失, 方便回收利用. 相似文献
8.
1 INTRODUCTION The chemistry of nickel complex with multi- dentate Schiff base ligands has attracted particular attention because this metal can exhibit several oxi- dation states[1]. Such complexes with different oxi- dation states play an important role in bioinorganic chemistry and redox enzyme systems[2], and many of them can provide the basis of models for active sites of biological systems or act as catalysts[3]. Nickel complexes with tetradentate N2O2 and tri- dentate N2O Schi… 相似文献
9.
合成了(R,R)-N,N'-dimethyl-N,N'-bis(2-pyridylmethyl)cyclohexane-1,2-diamine(R,R-mcp)及其相应的锰配合物,并将其锰配合物用于α,β-不饱和酮的不对称环氧化反应.考察了催化剂的量和氧化剂对反应的影响.并研究了在底物∶双氧水∶乙酸=1∶6∶5的条件下该催化剂的底物适用范围,获得了的56-70%的ee值. 相似文献
10.
JIAN Fang-fang ** XIAO Hai-lian XU Liang-zhong PANG Lei New Materials & Function Coordination Chemistry Laboratory Qingdao University of Science Technology Qingdao P. R. China 《高等学校化学研究》2004,20(6):725-728
IntroductionIn recentyears many efforts have been devotedto the preparation and characterization of pendant-arm macrocyclic complexes due to the fact that theligating groups attaching to the macrocyclic skele-ton can offer additional donor groups to maintainthe coordination sphere of metal centers in themacrocycles[1,2 ] .In this way,functionalised pen-dant- arm macrocyclic complexes have been de-signed and prepared so as to mimic the structureand properties of certain metalloenzymes and met-a… 相似文献
11.
Lan Yu Qi Wang Lu Dai Wei-Ying Li Rong Chen Mian HR Mahmood Hai-Yang Liu Chi-Kwong Chang 《中国化学快报》2013,24(6):447-449
Pseudo-first order reaction rate constants of 5,10,15-tris(pentafluorophenyl)corrole Mn(V)-oxo (F15CMn(V)-oxo),5,15-bis(pentafluorophenyl)-10-(phenyl)corrole Mn(V)-oxo(F10CMn(V)-oxo),5,15- bis(phenyl)-10-(pentafluorophenyl)corrole Mn(V)-oxo(F5CMn(V)-oxo) and 5,10,15-tris(phenyl)corrole Mn(V)-oxo(F0CMn(V)-oxo) with a series of alkene substrates in different solvents were determined by UV-vis spectroscopy.The results indicated that the oxygen atom transfer pathway between Mn(V)-oxo corrole and alkene is solvent-dependent. 相似文献
12.
Jun Lu Hai Yang Liu Lei Shi Xiang Li Wang Xiao Ying Lei Zhang Liang Nian Ji Lin Quan Zang Chi K. Chang 《中国化学快报》2011,22(1):101-104
The DNA nuclease-like activity of a water soluble manganese corrole 5,10,15-tris(N-methyl-4-pyridyl)- corrolatomanganese (Ⅲ)(Mn~ⅢTMPyC) has been investigated.Mn~ⅢTMPyC may bind strongly to DNA via outside groove binding mode as indicated by absorption spectra,viscosity measurements and CD spectra.Mn~ⅢTMPyC exhibited excellent catalytic activity in the DNA oxidative cleavage in the presence of hydroperoxide. 相似文献
13.
Hai Yang Liu Ling Chen Fei Yam Hai Ying Zhan Xiao Ying Xiang Li Wang Huan Feng Jiang Chi Kwong Chang 《中国化学快报》2008,19(8):1000-1003
The reductive demetalation of manganese corroles was investigated in CH2Cl2/HCl (aqueous) solvent by using SnCl2 as reducing agent. It was found that the demetalation yields depend on the substituents of corrole macrocycle significantly. Electron- rich manganese corrole undergoes reductive demetalation more easily than electron-deficient ones. The isolated reductive demetalation yield of manganese 5,10,15-tris(phenyl)corrole in present system is moderate (46%). As for electron-deficient Mn(Ⅲ) 5,10,15-tris(pentafluorophenyl)corrole, the acid-induced demetalation in HOAc-HESO4 (V/V = 3:1) is preferable with an isolated yield of 67%. 相似文献
14.
Two corrole xanthene ligands and four corresponding MnIV and CuIII complexes have been synthesized and spectroscopically characterized. This kind of complexes, comprising of xanthene and corrole linked by an amide bond, were designed as bio-inspired models for the oxygen evolving complex (OEC) in Photosystem II. We find that both manganese complexes 4a and 5a have efficiency on catalyzing oxygen evolution at low potential (about 0.80 V) by electrochemical method, which is a significant progress in the study of dioxygen formation. 相似文献
15.
Zeheng Yang Weixin Zhang Xue Wang Xiaogang Wen 《Journal of solid state chemistry》2006,179(3):679-684
Single-crystalline nanorods of β-MnO2, α-Mn2O3 and Mn3O4 were successfully synthesized via the heat-treatment of γ-MnOOH nanorods, which were prepared through a hydrothermal method in advance. The calcination process of γ-MnOOH nanorods was studied with the help of Thermogravimetric analysis and X-ray powder diffraction. When the calcinations were conducted in air from 250 to 1050 °C, the precursor γ-MnOOH was first changed to β-MnO2, then to α-Mn2O3 and finally to Mn3O4. When calcined in N2 atmosphere, γ-MnOOH was directly converted into Mn3O4 at as low as 500 °C. Transmission electron microscopy (TEM) and high-resolution TEM were also used to characterize the products. The obtained manganese oxides maintain the one-dimensional morphology similar to the precursor γ-MnOOH nanorods. Further experiments show that the as-prepared manganese oxide nanorods have catalytic effect on the oxidation and decomposition of the methylene blue (MB) dye with H2O2. 相似文献
16.
Mojtaba Bagherzadeh Reza Latifi Laleh Tahsini 《Journal of molecular catalysis. A, Chemical》2006,260(1-2):163-169
The catalytic activity of two manganese(III)-oxazoline complexes [Mn(phox)2(CH3OH)2]ClO4 and Mn(phox)3 (Hphox = 2-(2′-hydroxylphenyl)oxazoline), was studied in the epoxidation of various olefins. All of epoxidation reactions were carried out in (1:1) mixture of methanol:dichloromethane at room temperature using urea hydrogen peroxide (UHP) as oxidant and imidazole as co-catalyst. The epoxide yields clearly demonstrate the influence of steric and electronic properties of olefins, the catalysts and nitrogenous bases as axial ligand. [Mn(phox)2(CH3OH)2]ClO4 catalyst with low steric properties has higher catalytic activity than Mn(phox)3. The highest epoxide yield (95%) was achieved for indene at the presence of [Mn(phox)2(CH3OH)2]ClO4 within 5 min. The proximal and distal interactions of strong π-donor axial ligands such as imidazole with the active intermediate are efficiently increased activity of the catalytic system. 相似文献
17.
The investigations of complete nitrogen atom transfer reactions from (nitrido)manganese(V) salen to manganese(III) complexes of porphyrins and corroles revealed that stabilization of the [Mn(N)]2+ moiety is in the order of corrole > porphyrin > salen. The first kinetic examination of this quite fundamental reaction exposed a large solvent effect on both the enthalpy and entropy activation energies. Oxidation of the (nitrido)manganese(V) corroles leads to the first (nitrido)manganese(VI) complexes that are coordinated by tetrapyrrolic ligands. 相似文献
18.
Dr. M. Qadri E. Mubarak Dr. Hafiz Saqib Ali Jimei Zhou Prof. Chaoqun Li Prof. Jianliang Xiao Dr. Sam P. de Visser 《欧洲无机化学杂志》2023,26(5):e202200621
High-valent metal-oxo species are typical catalytic cycle intermediates in mono-oxygenases and dioxygenases and commonly react through oxygen atom transfer to substrates. In this work we study a biomimetic model complex with a 1,1’-bis((3,5-dimethylpyridin-2-yl)methyl)-2,2’-bipiperidine ligand system bound to a manganese(IV)-oxo(hydroxo) species and study its formation from manganese(II)-hydroxo and H2O2 as well as its reaction with (S)-1-phenylisochromane through dehydrogenative α-oxygenation. The work utilizes density functional theory methods to explore its catalytic cycle and its reactivity patterns. We show that the manganese(IV)-oxo(hydroxo) species is an active oxidant and preferentially the oxo group abstracts a hydrogen atom from substrate with barriers well lower in energy than those found for hydrogen atom abstraction by the hydroxo group. Interestingly, the rate-determining step is the OH rebound rather than the hydrogen atom abstraction, which would imply they would have limited kinetic isotope effect for the replacement of the transferring hydrogen atom by deuterium. 相似文献
19.
Feixiang Sun Jiamin Huang Dr. Zhihong Wei Prof. Dr. Conghui Tang Prof. Dr. Weiping Liu 《Angewandte Chemie (International ed. in English)》2023,62(26):e202303433
A homogeneous manganese-catalyzed cross-coupling of two secondary alcohols for the divergent synthesis of γ-disubstituted alcohols and β-disubstituted ketones is reported. Employing the well-defined Mn-MACHOPh as the catalyst, this novel protocol has a broad substrate scope with good functional group tolerance and affords a diverse library of valuable disubstituted alcohols and ketones in moderate to good yields. The strong influence of the reaction temperature on the selective formation of alcohol products was theorized in preliminary DFT studies. Studies have shown that the Gibbs free energy of the formation of alcohols is thermodynamically more favourable than corresponding ketones at a lower temperature. 相似文献
20.
Martin Bröring Prof. Dr. Christian Hell Melanie Steiner Carsten D. Brandt 《无机化学与普通化学杂志》2007,633(7):1082-1086
A set of porphyrinoid manganese(IV) complexes with the 2,3,7,8,12,13,17,18‐octaethyl‐5,15‐di‐p‐tolylcorrolato ligand [(oedtc)MnIVX] (X = Cl, Br, I) was prepared by oxidation of a manganese(III) precursor. The most unexpected complex in this series, [(oedtc)MnIVI], was found to display significant thermal stability despite the unusual MnIV‐I bond and could be investigated by X‐ray diffraction. Attempted ligand exchange reactions of the chlorido derivative with the pseudohalide anions cyanide, azide, cyanate and thiocyanate yielded the desired [(oedtc)MnIVX] complex only as the isothiocyanate derivative while for the other species the reduction to manganese(III) was observed. 相似文献