苯基磺酸官能化中孔硅基材料催化环己酮Aldol缩合反应

2-(1环-己烯基)环己酮是一种植物防腐杀菌剂,作为制备柑桔类水果的保鲜剂、分散染料染色的载体物质邻苯基苯酚(Ortho-phenylphenol,OPP)的原料而备受重视。其与环己叉基环己酮互为同分异构体,均由环己酮A ldol缩合反应合成,该过程是包括醇醛缩合、脱水在内的亲核加成-消除反应,     

新型光引发剂1-（6-邻氯苯甲酰基-9-乙基咔唑）-1-乙酮肟乙酯的合成

咔唑及其衍生物因其分子中有较大的共轭体系和较强的分子内电子转移特性,已在染料、农药及光学材料等领域得到较广泛的应用[1].     

4-氨基丁醇的高效合成方法

以2, 3-二氢呋喃为原料,先用酸性水溶液处理,得到的粗品再直接与盐酸羟胺发生反应,得到4-羟基丁基肟,再与还原试剂发生还原反应,最终高效得到4-氨基丁醇产品。此合成方法步骤短且易操作,产率高,可用于大量生产。     

From molecule to bulk material: optical properties of hydrogen-bonded dimers [C12H12N4O2AgPF6]2 and [C28H28N6O3AgPF6]2 depend on the arrangement of the oxime moieties

The dependence of the optical properties of [C(12)H(12)N(4)O(2)AgPF(6)](2) (dimer-1) and [C(28)H(28)N(6)O(3)AgPF(6)](2) (dimer-2) on the arrangement of the oxime moieties in the molecule and in bulk crystals was investigated by means of time-dependent density functional theory. Dimer-1 with simple pyridine oxime ligands and a wavy arrangement has a smaller dipole moment and larger transition energy between the two states, and thus smaller third-order polarizabilities and two-photon absorption cross sections. Dimer-2 with extended pyridine oxime ligands and a ladder arrangement has a larger dipole moment and smaller transition energy between the two states, and thus larger third-order polarizabilities and two-photon absorption cross sections. The lowest energy absorption band is red-shifted for dimer-2 as compared with dimer-1, due to more pronounced pi-pi delocalization interactions and weaker hydrogen bonding in dimer-2. The electronic absorption spectra, frequency-dependent third-order polarizabilities, and two-photon absorption cross sections involve significant contributions from charge transfers from pi/pi* orbitals of the pyridine oxime ligands but no contribution from PF(6) (-) ions or H(2)O molecules in the wavelength range studied for the monomers and dimers of the C(12)H(12)N(4)O(2)AgPF(6) and C(28)H(28)N(6)O(3)AgPF(6) molecules. The third-order susceptibilities and two-photon absorption coefficients of bulk solids were estimated on the basis of the optical properties of the corresponding dimers, and the bulk material constructed from dimer-2 has the larger optical parameters of the two.     

Synthesis of novel 1,4,7,10-tetraazacyclodecane-1,4,7,10-tetraacetic acid (DOTA) derivatives for chemoselective attachment to unprotected polyfunctionalized compounds

A convenient synthesis of novel bifunctional poly(amino carboxylate) chelating agents allowing chemoselective attachment to highly functionalized biomolecules is described. Based on the well known chelator 1,4,7,10-tetraazacyclodecane-1,4,7,10-tetraacetic acid (DOTA), we synthesized novel bifunctional chelating agents bearing additional functional groups by alkylating 1,4,7,10-tetraazacyclododecane (cyclen) with one equivalent of para-functionalized alkyl 2-bromophenyl-acetate and three equivalents of tert-butyl 2-bromoacetate. The resulting compounds, which contain an additional carbonyl or alkyne functionality, allow site specific labeling of appropriately functionalized unprotected biomolecules in a rapid manner via click reactions. This was demonstrated by the attachment of our new DOTA derivatives to the somatostatin analogue Tyr3-octreotate by chemoselective oxime ligation and CuI-catalyzed azide-alkyne cycloaddition. Initial biodistribution studies in mice with the radiometalated compound demonstrated the applicability of the described DOTA conjugation.     

一种可再生高选择性的硫化氢荧光探针

为了方便地检测环境样品中的硫化氢,利用香豆素酰肼肟配体构建了一个基于其铜配合物的可再生高选择性的硫化氢荧光探针(1-Cu²⁺)。 顺磁性Cu²⁺的荧光猝灭作用使探针的荧光很弱。 Na₂S溶液的加入可显著增强其荧光,其它常见阴离子(F^-,Cl^-,Br^-,I^-,CO32-,HPO42-,H₂PO4-,NO2-,NO3-,SO42-,CH₃COO^-,N3-,S₂O32-,CN^-)对配合物探针的荧光影响很小,共存时也不会干扰探针对硫化氢的增强响应。 Cu²⁺的加入能够再生探针(1-Cu²⁺),通过依次加入Cu²⁺和S^2- ,可重复地检测S^2-。 该探针响应时间快(~5 s),在0.5~5.0 μmol/L的范围内对H₂S响应呈线性,检测限低至37 nmol/L。     

一种同时测定环己酮肟水解反应中环己酮肟和硫酸羟胺含量的方法

在环己酮肟水解反应制备硫酸羟胺过程中,环己酮肟与产物硫酸羟胺在酸性条件下难以分离,硫酸羟胺的含量测定受到环己酮肟的干扰。 本文采用高效液相色谱法和氧化还原滴定法建立了一种简便、有效的新方法同时测定硫酸羟胺与环己酮肟的含量。 结果表明,在H⁺浓度大于2.4 mol/L,Fe³⁺/环己酮肟摩尔比大于5:1的条件下,环己酮肟和硫酸羟胺测定的标准滴定曲线的线性相关系数分别为0.99998和0.99996,相对标准偏差分别为0.39%和0.50%,水解反应样品的加标回收率为97.1%~100.6%。     

B2O3/TiO2-ZrO2催化环己酮肟气相Beckmann重排反应中的溶剂效应

 采用不同极性的溶剂作为环己酮肟的溶剂,考察了溶剂极性对B2O3/TiO2-ZrO2催化环己酮肟气相Beckmann重排反应性能的影响. 结果表明,除乙醇外,随着溶剂极性的增大,己内酰胺的收率逐渐提高. 在所考察的溶剂范围内,当采用极性最强的乙腈为溶剂时,B2O3/TiO2-ZrO2的催化性能最佳,连续反应9 h,环己酮肟的转化率为100%,己内酰胺的选择性高达98.6%. 极性较强的溶剂可显著改善B2O3/TiO2-ZrO2催化性能的原因主要是其有利于反应所生成的己内酰胺从催化剂表面快速脱附,从而可抑制己内酰胺进一步发生聚合及分解等副反应.     

Silicalite-1的后处理对其催化环己酮肟气相Beckmann重排反应性能的影响

 研究了silicalite-1分子筛的不同后处理方法对其催化环己酮肟Beckmann重排制己内酰胺性能的影响,这些方法包括水(或氨)蒸气处理以及在碱性、酸性或中性条件下用NH4NO3处理. 结合XRD,FT-IR和 29Si MAS NMR表征结果对silicalite-1催化剂的活性中心进行了探讨. 结果表明,碱性条件下用NH4NO3进行后处理对提高分子筛的催化性能最为有利. 分子筛上无规则排布的末端硅羟基数量的减少,以及具有相互氢键作用的邻式硅羟基的产生是其催化性能提升的主要原因.