Oxidative Bromination of Aromatic Compounds Using O-Iodoxybenzoic Acid with Tetraethylammonium Bromide

A mild and selective procedure for the bromination of activated arenes using o-iodoxybenzoic acid and tetraethylammonium bromide is presented. The reactions were carried out at room temperature and gave moderate to excellent yields.     

Bromination of Some Aromatic Compounds with Potassium Bromide in the Presence of Benzyltriphenylphosphonium Peroxodisulfate

A simple, efficient, and mild method for selective bromination of some activated aromatic compounds using potassium bromide in the presence of benzyltriphenylphosphonium peroxodisulfate in nonaqueous solution is reported. The results obtained revealed good to excellent selectivity between ortho and para positions of phenols and methoxyarenes.     

新型溴化烷基取代吡啶类季铵盐的合成

以烟酰胺(1)为原料,分别与1-溴代辛烷(2a)和1-溴代癸烷经烷基化反应合成了两个新型的溴化烷基取代吡啶类季铵盐(3a和3b),其结构经1H NMR,13C NMR,IR和HR-MS(MALDI)表征。在最佳反应条件[乙醇为溶剂,1 10 mmol,n(2a)∶n(1)=1.2,于78℃反应4 h]下,3a收率69%。     

Electrophilic Bromination of Alkenes,Alkynes, and Aromatic Amines with Iodic Acid/Potassium Bromide Under Mild Conditions

Bromination of alkenes, alkynes, and aromatic amines has efficiently been carried out at room temperature in short reaction times using HIO₃/KBr in CH₂Cl₂/H₂O (1:1) to prepare corresponding brominated compounds in excellent yields.     

N-甲基二乙醇胺三个季铵盐衍生物的合成与表征

以N，N－二甲基甲酰胺为溶剂，乙酸乙酯为催化剂，N－甲基二乙醇胺分别与苄基氯，十二烷基溴和十八烷基溴作用，得到了3个N－甲基二乙醇胺的季铵盐衍生物。采用IR，^1H NMR ^13C NMR和FAB MS对得到的衍生物的结构进行了表征。     

溴化铜对6-甲氧基-2-酰基萘的选择性溴化反应

甲氧基酰基萘;甲氧基溴酰基萘;溴化铜对6-甲氧基-2-酰基萘的选择性溴化反应     

Regioselective Bromination of Aromatic Amines and Phenols Using N-Benzyl-DABCO Tribromide

N-Benzyl-DABCO tribromide, a stable, solid organic ammonium tribromide, has been used as a bromine source for the regioselective and high-yielding bromination of aromatic amines and phenols. Mono-bromination proceeds well in the presence of a stoichiometric amount of bromine source at room temperature.     

十聚钨酸季铵盐的合成

利用离子液体首次合成两种十聚钨酸季铵盐{[Bmim]_4W_(10)O_(32)(Bmin=N-甲基-N'-正丁基咪唑)和[Bu~nPy]_4W_(10)O_(32)},其结构经TG,~1H NMR,~(13)C NMR,IR和元素分析表征.     

二氧化硅负载磷钨酸铵催化苯酚氧化溴代反应

以溶胶-凝胶法制备的二氧化硅负载磷钨酸铵为催化剂,溴化钾为溴源,双氧水为氧化剂,冰醋酸为溶剂,实现了苯酚的催化氧化溴代反应。 探讨了催化剂负载量、催化剂用量和反应时间等反应参数对氧化溴代反应的影响。 结果表明,溶胶-凝胶法制备的负载磷钨酸铵仍具有典型的Keggin结构;在室温的温和条件下,该催化剂表现出较强的催化苯酚氧化溴代反应活性和较高的对溴苯酚选择性,在实验优化条件下,苯酚转化率达到95.4%,对邻比达到3.2;而且催化剂易回收,重复4次使用后,催化活性有所降低,苯酚转化率为87.4%,对邻比为1.6。     

芳香胺和酚溴化的新工艺

研究了在室温下,N-溴丁二酰亚胺对芳香胺和酚的溴化工艺,在CHCl3、EtOH或EtOH/CHCl3溶剂中,用等摩尔的N-溴丁二酰亚胺可将某些芳香胺和酚(考察了5种反应底物)选择性地一溴化,产率92%~98%,N-溴丁二酰亚胺和反应底物摩尔比为2∶1;某些芳香胺和酚被专一地二溴化(考察了5种反应底物),产率90%~97%。 反应无须催化剂,投料后室温搅拌,反应条件温和,产品只需过滤洗涤即可纯化,操作简便。     

N,N-二甲基乙醇胺三个季铵盐衍生物的合成与表征

以N，N－二甲基甲酰胺为溶剂，乙酸乙酯为催化剂，N，N－二甲基乙醇胺分别与苄基氯、十二烷基溴和十八烷基溴作用，得到了3个N，N－二甲基乙醇胺的季铵盐衍生物。标题化合物结构经IR，^1H NMR,^13C NMRt FAB-MS表征。     

季铵盐掺杂聚苯胺电极的电容性能

采用循环伏安法,在铂电极表面聚合制备了季铵盐[CnH2n+1N(CH3)3]Cl(n=12,14,16,18)掺杂的聚苯胺修饰电极。 利用扫描电子显微镜、红外光谱以及X射线衍射对复合电极的表面形貌和结构进行了表征。 用循环伏安法、交流阻抗和恒电流充放电测试对电极的电化学性质和电容行为进行了系统研究。 结果表明,其中[C18H37N(CH3)3]Cl季铵盐掺杂的聚苯胺复合电极比表面积大,电容性能好,在2×10-3 A的充电电流下,初始比电容高达329.6 F/g,未掺杂电极比电容为199.0 F/g。 而且,复合电极的循环稳定性良好,经30次循环后比电容保持为252.4 F/g。     

Synthesis of Chitosan Quaternary Ammonium Salts

Chitosan has a wide scale of applications1-3. Interestingly, some antibacterial and antifungal activities have been described with chitosan and modified chitosan derivatives4-6. In polycationic biocides, generally, it is reasonably assumed7 that the charge density of the polyelectrolyte increases with increase in the molecular weight of its single coil, which leads to the enhanced adsorption of polycations onto the negatively charged cell surface. This is also favorable for the binding of t…     

金刚烷基甜菜碱型和季铵盐阳离子型表面活性剂的合成研究

以金刚烷胺为起始反应物,首先在过量甲酸存在下,与甲醛发生埃斯韦勒-克拉克甲基化反应合成了N,N-二甲基金刚烷叔胺,在此基础上通过N,N-二甲基金刚烷叔胺与氯乙酸钠、溴代正丁烷、溴代正辛烷、溴代十二烷、溴代十六烷等一系列季铵化试剂的季铵化反应,分别合成了N,N-二甲基金刚烷甜菜碱型表面活性剂及N-(1-金刚烷基)-N,N-二甲基正丁基溴化铵、N-(1-金刚烷基)-N,N-二甲基辛基溴化铵、N-(1-金刚烷基)-N,N-二甲基十二烷基溴化铵、N-(1-金刚烷基)-N,N-二甲基十六烷基溴化铵等金刚烷季铵盐阳离子型表面活性剂,产率分别为75%,75%,61%,44%,54%.采用元素分析,IR,1H NMR等分析手段对5种产物进行了结构鉴定,测试了各种金刚烷表面活性剂水溶液的表面张力.     

Synthesis of Alkyl-Aryl Ethers by Copper-catalyzed Etherization Reactions of Aryl Fluorides with Tetraalkylammonium Bromides and H2O

Synthesis of alkyl aryl ethers via copper‐catalyzed etherizations of electron‐deficient aryl fluorides with quaternary ammonium bromides and water has been developed. In the presence of Cu(OAc)₂, POPh₃ ( L4 ) and Cs₂CO₃, a variety of electron‐deficient aryl fluorides underwent the reaction with quaternary ammonium bromides and H₂O in moderate to good yields. The mechanism was also discussed.     

Composite Aromatic Boxes for Enzymatic Transformations of Quaternary Ammonium Substrates

Cation–π interactions to cognate ligands in enzymes have key roles in ligand binding and enzymatic catalysis. We have deciphered the key functional role of both charged and aromatic residues within the choline binding subsite of CTP:phosphocholine cytidylyltransferase and choline kinase from Plasmodium falciparum. Comparison of quaternary ammonium binding site structures revealed a general composite aromatic box pattern of enzyme recognition sites, well distinguished from the aromatic box recognition site of receptors.     

苯乙酮衍生物四苯硼季铵盐光产碱剂的合成

以苯乙酮衍生物、杂环叔胺和四苯硼盐为原料,合成了2个新的具有光活性的季铵盐光产碱剂,其结构经元素分析、IR和^1H NMR确证。     

芳醚的催化氧化反应

以取代芳醚为原料,碘苯醋酸酯为氧化剂,二氯甲烷为溶剂,在醋酸铑催化下合成了一系列醌类化合物,其结构经1H NMR,13C NMR和HR-MS确证。     

聚合物负载手性季铵盐的合成与表征

以金鸡纳生物碱中的辛可宁为原料,氯甲基化聚苯乙烯-聚乙二醇、一缩二乙二醇、二缩三乙二醇、乙二醇等为载体合成了几种聚合物负载的手性季铵盐,并对它们的结构用红外光谱、元素分析、扫描电镜和X射线光电子能谱等测试手段进行了表征。     

溴化四丁铵催化苯乙烯一步合成苯乙烯环状碳酸酯

以溴化季铵盐为催化剂, 通过苯乙烯的环氧化和CO2的加成反应一步直接合成出苯乙烯环状碳酸酯, 详细考察了催化剂的用量、氧化剂的种类、反应温度、反应时间和CO2压力等因素对反应主产物收率的影响. 结果表明, 以溴化四丁铵为催化剂, 于80 ℃和1 MPa CO2下反应6 h, 环状碳酸酯的收率达到38%, 这是季铵盐阳离子和亲核性阴离子协同催化的结果.