An efficient method for nitration of aromatic compounds over solid acid and polymer‐supported sodium nitrite

A variety of aromatic compounds are nitrated under heterogeneous conditions using a polymer‐supported hydrochloric acid, [P₄‐(VP)]HCl, with a polymer‐supported sodium nitrite, [P₄‐VP]NO₂, or sodium nitrite in ethanol at room temperature with high yields. This methodology is useful for nitration of activated aromatic compounds. In this procedure, the work‐up is very easy, and the spent polymeric reagent can be regenerated and reused. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

芳香硝基化合物的氟化

从反应原理、催化剂的选择、副反应的发生与控制等方面综述了芳香硝基化合物直接氟化的研究进展，阐述了硝基氟化的意义及应用重要性，介绍了硝基氟化的最新研究与发展方向。     

Synthesis of azo chromophores by using a polymer‐supported sodium nitrite

Polymer supported reagents especially anion exchange resins have been widely applied in organic synthesis. The recent developments in polymer‐supported reactions have led to the propagation of combinatorial chemistry as a method for the rapid and efficient preparation of novel functionalized molecules. An interesting and fast growing branch of this area is polymer‐supported reagents. In this study, diazonium salts are generated and are coupled with a coupling component by using a polymer supported nitrite and a polymeric acid. In this procedure, the azo chromophores are formed in a clean and efficient manner, the work‐up is easy and yields are high to excellent. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Selective reduction of aromatic nitro compounds over recyclable hollow fiber membrane‐supported Au nanoparticles

Guanidylated poly(2,6‐dimethyl‐1,4‐phenylene oxide) (GPPO) hollow fiber membrane (HFM) supported Au nanoparticles are prepared by a simple adsorption‐reduction of Au³⁺ with sodium borohydride as a reducing agent and polyvinyl pyrrolidone as a dispersant. The novel heterogeneous catalyst shows high catalytic activity for the reduction of various aromatic nitro compounds in an aqueous medium at room temperature and can be easily reused for several runs, for example, for the reduction of nitrobenzene, the yield reaches up to 92% even after 10 cycles, indicating the potential application of GPPO HFM as a catalysts support material for sustainable chemistry. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41268     

硝基化合物还原制备芳香胺工艺研究进展

综述了还原芳香族硝基化合物制备芳胺的主要方法,包括催化加氢法、金属还原法、水合肼还原法、电化学还原法等.在对4种还原反应机理概述的基础上,分别介绍了其应用情况及各自的优缺点.其中水合肼还原法由于其具有反应收率高、产品纯度高及无污染等优点越来越受到人们的关注.     

Removal of nitro aromatic compounds and sulfite acid from distillate of 2,4,6‐trinitrotoluene red water using modified porous polystyrene microspheres

To remove the nitro aromatic compounds (NACs) and SO₃^2? from distillate of 2,4,6‐trinitrotoluene (TNT) red water, the carboxylated and aminated polystyrene (PSt) microspheres were used as adsorbents. GC‐MS and HPLC analysis were used to determine the types and concentrations of NACs before and after adsorption. The carboxylated PSt, which was prepared by modifying PSt with phthlandione (PA), could remove the neutral NACs including 2,6‐dinitrotoluene (2,6‐DNT), 2,4‐dinitrotoluene (2,4‐DNT), 1,3,5‐trinitrobenzene (1,3,5‐TNB), and 2,4,6‐trinitrotoluene (2,4,6‐TNT), with the acid 2,4‐dinitrophenol (2,4‐DNP) and SO₃^2? remained in the distillate. The aminated PSt that was synthesized by activating PSt with chloroacetyl chloride follow by reaction with 1,2‐ethanediamine (EDA) could remove all the NACs and SO₃^2?. The results suggested that EDA‐PSt adsorbed the NACs though multimode interactions, i.e., hydrogen bond and electrostatic attraction. After adsorption using EDA‐PSt, chemical oxygen demand (COD) was reduced from 86.1 to 11.2 mg L^?1, and a colorless, transparent, and nontoxic solution with neutral pH value was obtained. Five grams of EDA‐PSt could purify 1600 cm³ of distillate of TNT red water, and the adsorbents could be recycled by elution with methanol to desorb the neutral NACs followed by elution with 0.1 mol L^?1 NaOH to wash off 2,4‐DNP and SO₃^2?. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

水中CuO-Al_2O_3催化水合肼还原芳香族硝基化合物

以NaOH溶液快速沉淀CuC l2和A lC l3的混合溶液制备了催化剂CuO-A l2O3,当n(CuO)∶n(A l2O3)=1∶2时所得催化剂性能最好。在水中,以邻硝基甲苯为底物,考察了几种因素对反应的影响。较优的反应条件为:4.11 g(30 mmol)邻硝基甲苯,3.53 g(60 mmol)水合肼,0.45 g CuO-A l2O3,80℃反应50 m in。在此条件下邻甲基苯胺的收率达到98%。在同样的条件下,CuO-A l2O3催化水合肼,几种还原芳香族硝基化合物得到相应的芳胺,收率90%~99%。     

A convenient synthesis of macroporous polymer‐supported supernucleophilic reagent and linear macromolecules

N,N′‐Bis(4‐pyridinyl)piperazine and N‐(4‐pyridinyl)piperazine have been prepared by treatment of piperazine with 4‐chloropyridine. N,N′‐Bis(4‐pyridinyl)piperazine (bis‐DMAP) is similar to a couple of 4‐(N,N‐dimethylamino)pyridine (DMAP). N‐(4‐Pyridinyl)piperazine as reactive group can be linked onto the macroporous polymeric carrier producing a polymer‐bound catalyst. A linear epoxy polymer containing the supernucleophilic functional groups have been synthesized by reaction of epichlorohydrin and 4‐aminopyridine. The linear polymeric catalysts have been braced by the macroporous resin to obtain a polymer‐supported linear polymeric catalyst. It is found that catalytic activity of bis‐DMAP approaches that of DMAP. The activity of the polymer‐supported linear polymeric catalyst is higher than that of the polymer‐bound catalyst in the acetylation of tert‐butyl alcohol, as monitored by gas–liquid chromatography. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 593–597, 2000     

Pd亚纳米簇@SiO2催化芳香硝基化合物加氢制芳胺

以新配制的硝酸钯溶液为原料，在十六烷基三甲基溴化铵/正丁醇/环己烷形成的反相微乳液体系中采用一锅法制备Pd亚纳米簇@SiO2核壳材料，得到质量分数达4%（以SiO2的质量计）、平均粒径为0.7 nm的Pd亚纳米簇。采用TEM、XRD、XPS、N2吸附-脱附对材料的物化性质进行了表征，探讨了其对芳香硝基化合物加氢制芳胺反应的催化性能。结果表明，在温和的反应条件下（50 ℃、1.0 MPa H2），催化剂Pd亚纳米簇@SiO2上硝基苯加氢反应4 h，苯胺的收率高达99.5%。在该催化剂上，其他多种芳硝基化合物加氢反应同样获得了较高的芳胺收率（98.5%~100%）。催化剂Pd亚纳米簇@SiO2循环4次后，活性无明显下降。     

水合肼法还原芳香硝基化合物制备芳胺的技术进展

综述了水合肼法还原芳香硝基化合物制备芳胺及其衍生物的近况,讨论了影响还原反应的主要因素和工艺条件,并展望了水合肼法制备芳胺工艺的应用前景和发展方向。     

硝酸铋和活性炭催化的水合肼还原芳香族硝基化合物制芳胺

研究了以硝酸铋和活性炭催化水合肼还原芳香族硝基化合物制备芳胺的反应.以硝基苯为底物,考察了硝酸铋和活性炭用量对反应的影响.结果表明,还原1 mmol硝基苯,Bi(NO3)3·5H2O和活性炭的适宜用量分别为0.06和0.1 g.在适宜的条件下,9种芳香族硝基化合物被还原为芳胺的收率为78%～99%.芳香族硝基化合物中取代基对反应结果有较大影响.催化剂的活性随使用次数的增加而下降,其活性下降的原因是硝酸铋的流失.     

FexOy@C负载Pt催化氯代硝基化合物加氢反应研究

以九水合硝酸铁为铁源,葡萄糖为炭源,通过水热法制备了FexOy@C复合材料。以该材料为载体,采用浸渍法制备了FexOy@C负载Pt催化剂,用于硝基化合物加氢制备相应苯胺。采用XRD和TEM对催化剂进行表征并探讨了催化剂的加入量、有机溶剂、混合溶剂体积比等因素对对氯硝基苯加氢制备对氯苯胺的影响。实验证明,该催化剂稳定性高,催化剂循环利用6次以后,其加氢活性仍可以达到100%,选择性可达99%以上。另外,该催化剂对其它硝基化合物也显示了较好的催化性能。     

Pd@CMP-1催化剂的制备及其催化硝基芳烃化合物的性能

以H₂PdCl₄为金属前体、共轭微孔聚合物(CMP-1)为载体,利用浸渍还原法首次合成了Pd含量为1%的负载型Pd@CMP-1加氢催化剂。以H₂为氢源、硝基芳烃化合物的加氢反应为探针,对催化剂的加氢性能进行了评价。用稀HNO₃对载体进行预处理,探究稀HNO₃对载体的影响。并通过XRD、TEM及BET等手段对催化剂进行分析表征,结果表明:Pd@CMP-1具有720m²/g的比表面积,Pd纳米颗粒均匀分散在载体CMP-1上,用稀HNO₃对载体进行预处理将改变CMP-1的结构性能,不利于催化剂的制备。考察了温度和压力对反应体系的影响,实验结果表明体系在2MPa、100℃条件下具有较高的反应活性。并通过几种硝基芳烃的加氢反应可知:Pd@CMP-1催化剂是一种高效环保的加氢催化剂,具有优秀的加氢性能以及一定的循环性能。     

Diazotization of anilines and diazo coupling with a coupling component mediated by a polymer‐supported sodium nitrite and a polymeric acid

Polymer‐supported reagents have become the subject of considerable and increasing interest as insoluble materials in the organic synthesis. In this study, diazonium salts are generated and are coupled with a coupling component by using a polymer supported nitrite and a polymeric acid. In this procedure, the azo chromophores are formed in a clean and efficient manner, the work–up is easy and yields are high to excellent. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

取代芳(硫)醚峭基物的水合肼催化还原研究

取代芳(硫)醚氨基化合物是重要的制药中间体,本文采用FeCl3.6H2O/C催化下水合肼还原取代芳(硫)醚硝基物,高收率、高纯度制得取代芳(硫)醚氨基化合物.该工艺具有操作方便、后处理简单等特点,反应过程易操控,对设备要求不高,安全可靠,对环境污染小,更适合于工业化生产.4个实例产物收率为85.0%～95.3%,GC纯...     

Synthesis and characterization of Ni nanoparticles-polyvinylamine/SBA-15 catalyst for simple reduction of aromatic nitro compounds

This work concerns the preparation and characterization of Nickel nanoparticle-PVAm/SBA-15, a polymer-inorganic hybrid composite, which was effectively employed as a novel heterogeneous catalyst for reduction of aromatic nitro compounds in the presence of NaBH₄ as a reducing agent. The reaction was carried out in room temperature and an aqueous medium. The catalyst showed good activity for the reduction of a number of aromatic nitro compounds yielding the respective amine compounds in excellent yield (~ 98%) at room temperature along with good reusability.     

Pt/PIC催化还原芳香硝基化合物制备芳胺

制备了一种多孔离子型高聚物(简称离聚物PIC),利用扫描电镜、透射电镜等一系列手段对离聚物PIC的形貌、结构进行表征,并制备负载型纳米铂催化剂(Pt/PIC)用于温和条件下芳胺(如对苯二胺、邻苯二胺、2-溴苯胺等)的合成实验中。实验表明:在1 atm H2条件下,该Pt/PIC催化剂对于芳香硝基化合物还原氢化反应具有高的催化活性和选择性,尤其是还原性基团如醛基、酮基、氰基,在氢化还原相应硝基芳基化合物过程中未受影响,且高产率得到相应芳胺。     

固相合成硒芳香杂环化合物

在室温下,分别由不同分子结构的芳香邻二胺与二氧化硒通过固相反应合成了2,1,3-苯并[c]硒二唑(BS)、5-甲基-2,1,3-苯并[3,4-c]硒二唑(MB)、2,1,3-萘并[2,3-c]硒二唑(NS)和7-羟基-1,2,5-硒二唑并[3,4-d]嘧啶(HSP)等硒杂环化合物。反应产率分别为BS：77．1％、MB：73．5％、NS：76．7％、HSP：50．5％;用红外吸收光谱(IR)和X-射线粉末衍射(XRD)对反应过程及产物进行监测和表征,并与液相反应合成的产物进行了对比;还用元素分析(EA)、感应耦合等离子体(ICP)分析化合物的元素组成。