钴卟啉的合成及其对氧还原的电催化性能

 合成了四苯基卟啉及其钴配合物,考察了催化剂、溶剂及反应温度等因素对四苯基卟啉收率的影响,并用红外光谱和核磁共振氢谱对合成产物进行了结构表征. 以X射线光电子能谱为主要手段,研究了不同热处理温度对钴卟啉结构的影响,通过测定空气电极极化曲线研究了热处理对钴卟啉催化活性的影响. 结果表明,在200 ℃, 以对硝基苯甲酸为催化剂,硝基苯为溶剂时,四苯基卟啉收率达32%. 热处理能提高金属卟啉的催化活性, 600 ℃热处理后,钴卟啉环中的 Co-N4 结构趋于键断裂的临界状态,催化活性点增多,催化活性较好; 而800 ℃处理的钴卟啉中部分 Co-N4 键破裂,催化活性下降.     

三氯化铁催化合成三芳基甲烷化合物的研究

三甲基芳烷类化合物在染料、生物、医药领域具有的重要应用价值。本文研究了2,4,6-三甲基苯甲醛和N,N-二甲基间溴苯胺通过缩合反应制备三芳基甲烷化合物,考察了催化剂种类、反应溶剂、反应温度和反应时间对产物收率的影响。确定合成条件为以无水Fe Cl3作为催化剂、对二甲苯为溶剂、反应温度为128℃,反应时间为32h,目标产物收率达到80%左右,产物结构经质谱和氢核磁共振谱表征确认。     

μ-氧代四苯基双核金属卟啉仿生催化剂的研究进展

综述了国内外及本课题组有关μ-氧代四苯基双核金属卟啉仿生催化剂合成及应用的最新研究进展和成果. 重点介绍了μ-氧代四苯基双核金属卟啉的合成方法, 即两步合成法、柱色谱分离法、一步合成法、自氧化法以及本课题组最新开发的一锅法. 其中一步合成法和自氧化法由于具有适用范围广、收率高等优点, 将成为μ-氧代四苯基双核金属卟啉的主要合成方法. 而一锅法尽管目前收率尚较低, 但由于其完全去掉了中间反应产物的分离和提纯以及原料和溶剂的损失, 而使工艺流程得到大大简化、能耗显著降低, 将成为一种极有发展潜力的合成方法. 系统地阐述了μ-氧代四苯基双核金属卟啉在仿生催化领域中的应用. 尤其是以μ-氧代四苯基双核金属卟啉为催化剂、O2或空气为氧化剂的催化氧化反应, 具有催化剂用量少、氧化剂清洁且廉价易得、无需助催化剂和共还原剂、反应条件温和等优点, 将成为未来仿生催化氧化领域研究的前沿和热点.     

磷钨酸离子液体催化合成N-苯基邻苯二甲酰亚胺的研究

以邻苯二甲酸酐为原料,以磷钨酸离子液体为催化剂合成了N-苯基邻苯二甲酰亚胺。通过对溶剂、反应温度、催化剂用量的研究,探索了磷钨酸离子液体催化反应条件和催化剂循环使用效果。结果表明,催化合成的最佳反应条件是:甲苯作为溶剂,催化剂用量为0.20 mmol,反应温度为100℃。催化剂循环使用6次后催化剂损失率小于0.01%。该方法实现了N-苯基邻苯二甲酰亚胺的绿色合成。     

固体酸催化二氟二苯甲酮和苯胺缩合合成N-(双(4-氟苯基)亚甲基)苯胺

以固体酸为催化剂,4,4’-二氟二苯甲酮与苯胺脱水缩合,合成了N-(双(4-氟苯基)亚甲基)苯胺.比较了不同固体酸催化剂H型ZSM-5、Na型ZSM-5、介孔分子筛MCM-41(Al)及强酸型离子交换树脂Amberlyst 15的催化效果.使用比表面、NH3-TPD对催化剂进行了表征,并与催化效果关联.考察了催化剂用量、原料摩尔比、浓度及溶剂等反应条件对产物收率的影响.产物通过熔点、核磁共振谱进行了表征.结果表明,HZSM-5固体酸催化剂具有优异的催化作用.在优化条件下,以对二甲苯为反应溶剂和脱水剂,4,4’-二氟二苯甲酮0.1 mol,苯胺0.2 mol,催化剂用量2.0 g,反应24 h,产物收率达91%.此外,催化剂易于分离,能够重复使用多次.     

苯甲酰咪唑过氧化反应

以苯甲酰咪唑和叔丁基过氧化氢为反应物,1,8-二氮杂二环十一碳-7-烯(DBU)为催化剂,乙睛(CH₃CN)作为反应溶剂,合成了过氧化叔丁酯类化合物。 分别考察了不同催化剂及其用量、原料配比、溶剂、温度和时间对反应的影响,在最优条件下,共得到25个目标产物,收率范围为45%~99%。 目标化合物经核磁共振氢谱、核磁共振碳谱以及质谱进行了结构表征。 该方法具有操作简单、反应条件简单温和、产物收率高及底物适用性好等优点,为过氧化叔丁酯类化合物的合成提供了新的思路。     

原位酸树脂催化合成丙烯酸高碳烷基酯

以原位酸树脂为催化剂合成了丙烯酸高碳烷基酯。探讨了酸醇摩尔比、催化剂用量、阻聚剂对苯二酚用量、反应温度、反应时间等对反应产物收率的影响。结果表明,高碳烷基醇与丙烯酸摩尔比1:1.2,催化剂和阻聚剂用量分别为高碳烷基醇质量的5.0%和0.8%,反应温度为140℃,反应时间为6h,产物收率为90.0%～97.0%,产物纯度为92.00%～98.00%。催化剂经甲醇活化,循环使用5次后产品收率为75.0%。该研究为丙烯酸高碳烷基酯的合成提供了一种新的方法。     

苯基脲与甲醇合成苯氨基甲酸甲酯的研究

采用苯基脲与甲醇反应合成了苯氨基甲酸甲酯,考察了不同催化剂、原料配比及反应工艺条件的影响,确定了适宜的合成条件,并根据产物分布对催化反应机理进行了初步探讨.结果表明,以PbO为催化剂,于140℃反应4h后,苯基脲转化率为95.2%,苯氨基甲酸甲酯收率为80.6%.     

2-甲酰基-meso-四苯基卟啉的合成

研究了以金属四苯基卟啉为原料,经由Vilsmeier甲酰化反应制备2-甲酰基-meso-四苯基卟啉的合成方法。不同金属离子、溶剂以及Vilsmeier反应时间等因素对目标化合物的最终收率影响很大。在以铜四苯基卟啉为原料、氯仿为溶剂及Vilsmeier反应时间为5 h的反应体系中,目标化合物的收率可以高达99%以上。     

无卤阻燃剂新戊二醇基苯基磷酸酯的合成与性能

采用氯化磷酸单苯酯(MPCP)和新戊二醇(NPG)为原料,以4-二甲氨基吡啶(DMAP)为催化剂,以四氢呋喃为溶剂,合成了一种含有新戊二醇结构的环状磷酸酯无卤阻燃剂新戊二醇基苯基磷酸酯(NGPP),并研究了其对环氧树脂阻燃性能的影响.反应收率可达81.2%.产物的结构经核磁、红外和质谱进行了表征.热分析表明,NGPP的起始热分解温度和最大热分解温度分别为189.0℃和259.4℃.NGPP在不饱和聚酯树脂中表现出较好的阻燃性能,且在添加适量三聚氰胺后阻燃性能进一步提高.     

Study on the alkylation reaction of guanine and N-acetylguanine and the synthesis of 1''''-C alkylated carba-DHPG analogues

The alkylation reaction of guanine and N-acetylguanine with model compounds such as isopropyl bromide or 4-heptyl tosylate were studied. The reaction conditions such as temperature, solvent, base, and catalyst were examined for their effects on the reaction rate, and the yield and regioselectivity of the coupling reaction. The highest yield was obtained by using DMSO as the solvent. The reaction proceeded in a homogenous manner to give higher yield of 9-N and 7-N substituted product in a mole ratio of 1:1. The ratio could be raised to 2:1 if dibenzo-18-crown-6 was used as a catalyst. Using the above procedure, three carba-DHPG analogues bearing different 1'-C alkyl side chains were synthesized.     

Effects of the polymer-support on the synthesis of 2,4-dibromophenyl allyl ether in a triphase catalysis

The synthesis of 2,4-dibromophenyl allyl ether by reacting allyl bromide with 2,4-dibromophenol in an organic solvent/alkali solution by triphase catalysis was studied. A macroporous polymer pellet which served as the support of the catalyst was prepared by reacting styrene monomer with chloromethyl styrene and divinylbenzene through suspension polymerization. Tri-n-butylamine was immobilized on the surface of the polymer pellet to form the triphase catalysts. Immobilization of the catalyst on the polymer support carried out in a mechanical agitator was suggested to obtain a high catalyst reactivity. In the three-phase reaction, the effects of agitation speed, and the characteristics of the catalyst pellet which affect the conversion of allyl bromide in the three-phase catalytic reaction were examined in detail. Based on the experimental data, the optimum operating parameters for preparing the triphase catalyst to get a high yield of 2,4-dibromophenyl allyl ether were: using a low degree of polymer crosslinking (2%), and small particle size. The yield of the product obtained from the present study is higher than that which was obtained in a two-phase reaction. © 1993 John Wiley & Sons, Inc.     

Aryl-guanidine/Pd-catalyzed Suzuki Cross-coupling Reaction at Room Temperature

Four aryl-guanidines(AG)were synthesized and used for the palladium-catalyzed Suzuki cross-coupling reaction to test the catalytic activity.In the presence of steric bulk AG,when aryl bromide and arylb...     

钯催化的酰胺羰化反应研究-溶剂的影响

考察了不同溶剂(如N-甲基吡咯烷酮、乙腈、聚乙二醇、1-甲基-3-己基咪唑六氟磷酸盐)以及不同共催化剂(如十六烷基三甲基溴化铵、四丁基溴化铵、溴化锂)对苯甲醛酰胺羰化反应的影响.与使用高沸点的有机溶剂N-甲基吡咯烷酮相比,使用乙腈、聚乙二醇和1-甲基-3-己基咪唑六氟磷酸盐作溶剂,反应后处理过程大大简化,反应界面更加友好.聚乙二醇作溶剂首次应用于酰胺羰化反应.     

2-烯丙基-1,1-偕二金属环己烷的合成研究

在无水乙醚中－１－锂代环已烯和烯丙基溴化镁于为水溴铧锌作用下发生金属化克兰节省理排反应,生成２－烯丙基－１,１－偕二金属环乙烷。通过对温度１溶剂量物凤料顺序等重排反应主要影响因素的考察和优化,可使２－烯丙基－１,１－偕二环已烷的收率达到６５％。     

Photochemistry of 3- and 5-phenylisothiazoles. Competing phototransposition pathways

5-Phenylisothiazole undergoes phototransposition via the electrocyclic ring closure-heteroatom migration pathway and by the N(2)-C(3) interchange reaction pathway. The latter route is enhanced by the addition of triethylamine (TEA) to the reaction medium and by increasing the polarity of the solvent. In addition to phototransposition, 5-phenylisothiazole also undergoes photocleavage to 2-cyano-1-phenylethenethiol which was trapped by reaction with benzyl bromide to yield 2-cyano-1-phenylethen-1-ylbenzyl thioether. 3-Phenylisothiazole also phototransposes by both reaction pathways, but the product distribution is not affected by the addition of TEA or by changing the solvent polarity.     

Comparaison de la reactivite du bromure d'ethylmagnesium et du diethylmagnesium vis-a-vis des cetones α,β-ethyleniques dans divers solvants

The reactivity of diethylmagnesium and ethylmagnesium bromide towards 2-cyclohexenone in various solvents is studied. The 1,2 addition is always predominant, but diethylmagnesium adds almost exclusively in 1,2 manner to this ketone while ethylmagnesium bromide gives both 1,2 and 1,4 addition products with a ratio dependent of the solvent basicity. Thus, in hydrocarbons (hexane, benzene), the magnesium reagents behave similary; and with more basic solvents, for EtMgBr the yield of the 1,4 addition product increases and that of the 1,2 addition product decreases.With another α,β-ethylenic ketone, trans-3-penten-2-one, 1,4 addition occurs predominantly with both magnesium reagents, diethylmagnesium and ethylmagnesium bromide, but diethylmagnesium gives again much more 1,2 addition product than ethylmagnesium bromide.     

二甲基烯丙基苄基氯化铵的合成及表征

用氯化苄与二甲基烯丙基胺为原料合成了二甲基烯丙基苄基氯化铵,研究了光照、温度、原料配比、反应时间和溶剂等因素对反应产率的影响,确立了最佳反应条件,并对产物的结构进行了表征.     

An efficient synthetic-route to prepare [2,3,6-tri-O-(2-bromo-2-methylpropionyl]-β-cyclodextrin)

The efficient approach for the synthesis of [2,3,6-tri-O-(2-bromo-2-methylpropionyl]-β-cyclodextrin) (21Br-β-CD) is described. The reaction between 2-bromoisobutyric bromide and β-cyclodextrin was performed directly in 1-methyl-2-pyrrolidione solvent, leading to much less complicated procedures and higher yield (up to 89.5%) compared with those reported previously (17% yield). The product is an extremely useful initiator in synthesizing star polymers with well-defined structures using atom transfer radical polymerization for biomedical applications.     

氟喹诺酮作为钯催化Heck反应有效配体的研究

研究了氟喹诺酮作为钯催化Heck反应的有效配体. 碘苯、溴苯和其它芳基卤衍生物与丙烯酸丁酯、苯乙烯等取代乙烯类化合物在钯和氟喹诺酮的催化下发生Heck反应. 讨论了配体、催化剂用量、碱和溶剂对Heck反应产率的影响. 该反应的最优化条件是: 钯源为Pd(OAc)2 (0.1 mol%), 诺氟沙星作为配体(0.2 mol%), K2CO3作为碱, DMA作为溶剂, 取代碘苯及溴苯和它们的衍生物与丙烯酸丁酯、苯乙烯等乙烯基化合物的反应均可以得到高收率的目标偶联产物.