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1.
研究了次氯化血红素在乙酸酐、氢溴酸体系中脱铁制备次卟啉的新方法。 考察了反应时间、温度以及乙酸酐和氢溴酸与次氯化血红素的比例对反应产率的影响,讨论了其脱铁机理。 实验结果表明,当次氯化血红素与氢溴酸和乙酸酐的摩尔比为1∶6.3∶61.2,温度为100 ℃,反应2 h时,脱铁产率高达96.3%。 合成了一系列金属次卟啉配合物,考察了溶剂对卟啉配合金属难易程度及金属离子对卟啉S带和Q带的影响。 用电喷雾串联质谱(ESI-MS-MS)、UV-Vis和IR表征了目标产物的结构。  相似文献   

2.
以氯化血红素(Ⅰ)为原料,经过溴化氢-冰醋酸加成反应、羟基亲核取代反应和无水氯化氢催化酯化反应制得3,8-双-(1-羟基乙基)次卟啉二甲酯(Ⅲ),然后通过琼斯试剂氧化反应制备了3,8-双乙酰基次卟啉二甲酯(Ⅳ)。 考察了血红素与溴化氢-冰醋酸饱和溶液反应过程中温度和时间对3,8-双-(1-羟基乙基)次卟啉二甲酯(Ⅲ)产率的影响;改进了酯化反应的实验条件;选用了廉价易得、选择性较好的羟基选择性氧化剂。 实验结果表明,当反应温度为35 ℃、反应时间为25 h时,血卟啉(Ⅱ)的产率最高,为98.5%;当催化剂为无水氯化氢时产物(Ⅲ)的产率最高,为72.1%;使用琼斯试剂做氧化剂使实验成本大大降低。 通过1H NMR、MS和IR测试技术对产物结构进行了表征。  相似文献   

3.
以氯化血红素为原料, 经过脱铁、酯化、催化加氢和络合金属得到仿生催化剂Co(Ⅱ)-3,8-二乙基次卟啉二甲酯. 在无其它外加溶剂及共还原剂的条件下, 将其应用到催化空气氧化环己烷反应, 将实验结果同Co(Ⅱ)原卟啉二甲酯催化氧化空气氧化环己烷的结果进行对照, 并对催化氧化的机理进行了初步研究. 实验结果表明, Co(Ⅱ)-3,8-双乙基次卟啉二甲酯克服了Co(Ⅱ)原卟啉二甲酯3,8-位乙烯基取代基不稳定的缺点, 能够很好催化空气氧化环己烷, 环己醇和环己酮的总收率达16.9%.  相似文献   

4.
以氯化血红素(Ⅰ) 为原料, 经过脱铁、 酯化、 催化加氢、 水解、 酸胺缩合以及络合金属合成了化合物Co(Ⅱ)-[2,7,12,18-四甲基-3,8-二乙基-13,17-丙酰基氨乙基联二硫基乙氨基甲酰乙基-29,34-二甲氧甲酰基]-卟啉[Co(Ⅱ)MPDTEP, V]. 对产物的结构行了表征, 分析了反应时间和反应温度对化合物[2,7,12,18-四甲基-3,8-二乙基-13,17-丙酰基氨乙基联二硫基乙氨基甲酰乙基-29,34-二甲氧甲酰基]-卟啉(MPDTEP, Ⅳ)产率的影响. 将化合物Ⅴ通过自组装修饰于金电极表面, 修饰的金电极通过傅里叶红外光谱(FTIR)和电化学方法进行表征, 研究了其对氧气的电催化还原效果.  相似文献   

5.
靳丽丽  常涛  景欢旺 《催化学报》2007,28(4):287-289
研究了钌卟啉络合物催化二氧化碳与环氧化合物的偶联反应,考察了不同钌卟啉络合物、助催化剂、反应温度、催化剂用量及不同共催化剂对二氧化碳与环氧化合物偶联反应的影响.结果表明,当以Ru(TPP)(PPh3)2为催化剂,重氮乙酸乙酯为助催化剂,苯基三甲基三溴化铵为共催化剂,且底物∶催化剂∶助催化剂∶共催化剂摩尔比为200∶1∶1∶2,反应温度为323 K时,不同环氧化合物都取得了较高的环碳酸酯产率.  相似文献   

6.
次卟啉二甲酯钴络合物均相选择性催化氧化环己烷   总被引:2,自引:0,他引:2  
以次卟啉二甲酯钴[Co(DPDME)]为仿生催化剂,分子氧(空气)为氧给体,无其它辅助催化剂的条件下研究了催化氧化环己烷的反应。考察了反应温度、空气压力、催化剂用量和卟啉配体结构对醇酮的产率及选择性的影响。结果表明,在相同条件下,次卟啉二甲酯钴的催化活性明显高于其它的钴卟啉催化剂。以次卟啉合钴为催化剂,浓度为0.015 mmol/L,反应温度423 K,在空气压强为0.8 MPa的条件下反应5 h,环己烷的转化率达到18.17%,选择性为87.43%。温度对次卟啉钴的催化活性影响较大,温度高于443 K时,催化剂的稳定性降低,但是其转化数仍达到了66 646。对次卟啉二甲酯钴催化空气氧化环己烷的反应路径作了初步探讨。  相似文献   

7.
[2;7;12;18-四甲基-13;17-双(-2甲氧基羰基乙基)]-次卟啉铜(Ⅱ)的合成;氯化血红素;次氯化血红素;四甲基二氢卟啉二丙酸甲酯;[四甲基二(甲氧基羰基乙基)]卟啉铜(Ⅱ);合成  相似文献   

8.
铁卟啉化合物的合成及其催化环己烷羟基化反应的研究   总被引:1,自引:0,他引:1  
合成了15种卟啉环上具有不同取代基和纵轴上具有不同配位基的TRPPFe^ⅢCl和TPPFe^ⅢX, 从反应速率、反应产率和产物选择性等方面考察了卟啉环上取代基R和纵轴配位基X对这些铁卟啉在温和条件下催化环己烷羟基化反应催化性能的影响,还研究了反应溶剂、反应温度以及有机碱等环境因素对铁卟啉催化性能的影响,获得了一些新的结果和规律。  相似文献   

9.
吕艳阳  刘小玉  曹俊 《应用化学》2010,27(6):691-694
利用自制的四(对甲氧基苯基)卟啉,与氯化钐在四氢呋喃溶剂中反应,得到一个未见文献报道的四(对甲氧基苯基)卟啉钐(Ⅲ)化合物。 利用UV-Vis、IR、1H NMR 及元素分析测试技术对化合物结构进行了表征,并对其配位反应条件、配体及配合物的荧光性能进行了研究。 反应条件简单,易于操作,产率为62.4%。  相似文献   

10.
扈靖  刘彦钦  韩士田 《应用化学》2012,29(5):608-610
以二环己基碳二亚胺为脱水剂,meso-四(对羟基苯基)卟啉与5-氟尿嘧啶-1-基乙酸反应,合成了一种新型meso-四[4-(5-氟尿嘧啶-1-基乙酰氧基)苯基]卟啉化合物(A),产率12.7%;将其与乙酸锌反应得到其锌配合物(B),产率30.8%。 通过1H NMR、IR、MS、UV-Vis及元素分析确证了卟啉化合物A及其锌配合物B的结构。  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.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
19.
《Tetrahedron》2014,70(21):3377-3384
The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.  相似文献   

20.
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   

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