香兰素Schiff碱及其异构体分子特性的预测研究

利用Gaussview程序模拟构造香兰素Schiff碱及其3种异构体的分子结构,并利用量化计算软件Gaussian03密度泛涵方法在(B3LYP/6-31G)基组水平上,优化4种Schiff碱的分子结构及计算频率。根据前线轨道理论及原子净电荷等相关量化参数,估计化合物及其异构体分子的稳定性、活性部位、不同原子金属配位能力及亲核反应的作用点等分子特性。     

双水杨醛类缩乙二胺席夫碱的合成及光谱性能

以水杨醛为原料,通过硝化或溴化反应合成了3,5—二硝基水杨醛(p.m57℃～59℃),5—溴水杨醛((m.p104℃～105℃),3—硝基水杨醛(m.p124℃～127℃),和3—溴—5—硝基水杨醛(m.p148℃～149℃)收率分别为76.0%、81.8%、63.0%和80.5%用水杨醛及其衍生物同乙二胺反应制备出11种双水杨醛缩乙二胺席夫碱。采用~1H—NMR对合成的系列席夫碱进行了表征,通过紫外光谱测定席夫碱中苯环上不同取代基对紫外吸收波长的影响。     

分子筛固载席夫碱金属配合物的催化氧化性能研究

以NaX-13型分子筛为载体,固载一种新型五齿含氮、氧席夫碱金属配合物,考察了NaX-13型分子筛固载镍、铜席夫碱金属配合物(Msalnpyen/NaX)在不同反应条件下,对苯乙烯氧化成苯甲醛反应的催化性能,并得到了适宜的催化反应条件。     

微波辐射下1, 2, 4-三唑硫酮席夫碱衍生物的合成及表征

微波辐射条件下,以自制的氨基均三唑硫醇与查尔酮为原料, 通过亲核取代反应,制备了氨基均三唑氮代二苯丙酮(4),(4)与系列芳香醛经缩合反应合成了7种未见文献报道的三唑硫酮席夫碱5a~5g。探讨了原料摩尔比、催化剂用量、反应时间、溶剂、微波辐射功率对收率的影响,得到了优化的工艺条件：n(芳醛): n(氨基三唑硫酮)=1:1,微波功率500 W,催化剂冰醋酸2ml,反应时间5~7min,溶剂为DMF, 收率为71%~87%。利用IR、MS、1H NMR、元素分析对合成中间体和目标产物进行了结构表征。     

含氟Schiff碱的无溶剂法合成与结构表征

无溶剂无催化剂条件下,2-(4-氨基苯基)六氟异丙醇和苯甲醛类物质经室温研磨得到了系列含氟Schiff碱化合物。产物结构经EA、IR、1HNMR和MS确认。结果表明,采用无溶剂法,反应时间可由常规溶液法的90～240 min缩短至10～50 min,目标物收率由71%～87%提高至98%～99%。     

新型不对称席夫碱的合成与表征

以间苯二酚、乙酸酐为原料,制备中间体2,4-二羟基-1,5-苯二乙酮(4,6-二乙酰基间苯二酚).利用控制反应物配比的方法,合成不对称席夫碱4,6-二乙酰基间苯二酚缩邻苯二胺缩水杨醛,并用红外光谱、核磁共振氢谱、质谱对其结构进行了表征.     

高羰基含量水溶性氧化淀粉-氨基噻唑希夫碱的合成及吸附性能

以次氯酸钠氧化制备的高羰基含量水溶性氧化淀粉为原料合成了水溶性氧化淀粉——氨基噻唑希夫碱(OSAT),确定最佳反应条件为:N2保护、水为溶剂、乙酸调节pH、初始pH=5、反应温度70℃、反应时间16 h。通过调节氨基噻唑与羰基的比例调控氨基噻唑取代度,醛基利用率100%。通过FTIR、NMR和UV对OSAT的结构进行了表征。研究了OSAT对Cu2+、Ag+的吸附性能,结果表明取代度为0.14的OSAT对Cu2+、Ag+的吸附量分别为1.18、1.48 mmol/g。     

Host (nanocavity of zeolite-Y)/guest (Mn(II), Co(II), Ni(II) and Cu(II) complexes of pentadendate Schiff-base ligand) nanocomposite materials (HGNM): application in the heterogeneous oxidation of cyclohexene

Transition metal (M = Mn(II), Co(II), Ni(II) and Cu(II)) complexes with pentadendate Schiff-base ligand; N,N′-bis(salicylidene)-2,6-pyridinediaminato, H₂ [sal-2,6-py]; was entrapped in the nanocavity of zeolite-Y by a two-step process in the liquid phase: (i) adsorption of bis(salicylaldiminato)metal(II); [M(sal)₂]-NaY; in the supercages of the zeolite, and (ii) in situ Schiff condensation of the metal(II) precursor complex with the corresponding 2,6-pyridinediamine; [M(sal-2,6-py)]-NaY. The new materials were characterised by several techniques: chemical analysis, spectroscopic methods (DRS, BET, FTIR and UV/Vis), conductometric and magnetic measurements. Analysis of the data indicates that the M(II) complexes are encapsulated in the nanodimensional pores of zeolite-Y and exhibit different from those of the free complexes, which can arise from distortions caused by steric effects due to the presence of sodium cations, or from interactions with the zeolite matrix. The Host–Guest Nanocomposite Materials (HGNM); [M(sal-2,6-py)]-NaY; catalyzes the oxidation of cyclohexene with tert-butylhydroperoxide (TBHP). Oxidation of cyclohexene with HGNM gave 2-cyclohexene-1-one, 2-cyclohexene-1-ol and 1-(tert-butylperoxy)-2-cyclohexene. [Mn(sal-2,6-py)]-NaY shows significantly higher catalytic activity than other catalysts.     

The enhancing power of iodide on corrosion prevention of mild steel in the presence of a synthetic-soluble Schiff-base: Electrochemical and surface analyses

The inhibitory action of N,N′-1,3-propylen-bis(3-methoxysalicylidenimine) {PMSI} on mild steel corrosion in sulfuric acid medium was investigated through electrochemical methods and evaluations based on infrared spectroscopy and scanning electron micrographs. The studies revealed that the molecule is a good mixed-type inhibitor (mostly anodic), acts as a multi-dentate ligand and repels the corrosive agents by hydrophobic forces. Its adsorption on metal surface has a physicochemical nature and obeys the Langmuir isotherm. At a critical (optimum) concentration, an anomalous inhibitory behavior was observed and interpreted at microscopic level by means of desorption/adsorption process and horizontal ↔ vertical hypothesis. The addition of iodide into acid moreover causes a synergistic influence, a substantial enhancement on inhibitory performance. Finally, using isolated inhibitor calculations at B3LYP/6-31G + (d,p) level of theory, the equilibrium geometry of PMSI was determined and the energy required for hindrance avoidance was predicted.     

希夫碱催化剂催化丙交酯本体开环聚合

合成了希夫碱催化剂,并成功地催化丙交酯本体开环聚合。结果表明,希夫碱催化剂催化合成聚乳酸可达到较高的转化率（高于95％）。研究了单体与催化剂物质的量比、聚合时间及聚合温度对该催化剂催化丙交酯本体开环聚合反应的转化率及所得聚乳酸相对分子质量的影响。当单体与催化剂物质的量比为400,聚合时间24h,聚合温度140℃时,可得到黏均相对分子质量Mq=8．439×10^4的聚乳酸。