A computational study into the reactivity of epichlorohydrin and epibromohydrin under basic conditions in the gas phase and solution

Ab initio molecular orbital calculations were carried out on epibromohydrin (EBH) and epichlorohydrin (ECH) in an attempt to elucidate their reactivity with respect to a hard nucleophile, hydroxide. These systems were modeled in both the gas phase and a polar solvent under basic conditions. In the gas phase, it was determined that a direct displacement mechanism (nucleophilic attack at the C1 position) was operative for EBH, while an indirect pathway (nucleophilic attack at the C3 position and subsequent intramolecular displacement) was followed for ECH. In an acetone solution, only the indirect displacement mechanism was found to occur. An electrostatic argument is advanced to account for this behavior in polar solution. Copyright © 2007 John Wiley & Sons, Ltd.     

气相法分析3-氯-2-羟丙基三甲基氯化铵中的微量有机杂质

 以氯仿为萃取剂 ,对 3 氯 2 羟丙基三甲基氯化铵 (CHPTMA)水溶液进行萃取 ,用气相法分析了CHPT MA溶液中的微量有机杂质环氧氯丙烷和 1 3 二氯丙醇。柱为 2m× 3mmi d 的不锈钢填充柱 ,固定相为10 %的PEG 2 0M ,载体为ChromosorbW/AW。环氧氯丙烷和 1,3 二氯丙醇的回收率分别为 97 5 %～ 10 5 0 %和93 3%～ 98 8% ,相对标准偏差分别为 11 5 %和 13 1% ,最低检测限分别为 5 0 μg/g和 10 0 μg/ g。     

系列单取代烷氧基-2-羟丙基-β-环糊精的合成与表征

以环氧氯丙烷和脂肪醇为原料, 通过相转移催化法合成了乙基、正丙基、正丁基和正戊基缩水甘油醚(1～4), 并利用所合成的缩水甘油醚和β-环糊精为原料, 分别在弱碱水溶液(1.5%)和强碱水溶液(30%)中制备并用硅胶柱分离出单2位取代的乙氧基、丙氧基、丁氧基和戊氧基-2-羟丙基-β-环糊精(1a～4a)和单6位取代的丙氧基、丁氧基和戊氧基-2-羟丙基-β-环糊精(2b～4b), 利用薄层色谱、红外光谱、差热扫描量热分析、质谱和核磁共振等手段对所合成的产品进行了表征.     

乙酰丙酮钇催化环氧氯丙烷的均聚合与共聚合

用过渡金属络合催化剂聚合环氧氯丙烷能获高分子量的聚合物。稀土络合催化剂对环氧乙烷,环氧丙烷及环硫丙烷的开环聚合具有明显效果。本文选用Y(acac)_3-H_2O-Al(i-Bu)_3催化剂,考察环氧氯丙烷的均聚合及其与环氧乙烷,环氧丙烷的共聚合,并用核     

β-Cyclodextrin epichlorohydrin copolymer as a solid-phase extraction adsorbent for aromatic compounds in water samples

A novel solid-phase extraction (SPE) procedure for trace aromatic compounds in water samples has been developed using 12 aromatic compounds as model compounds and GC-MS and UV spectrophotometry for detection. The method is based on the fact that β-cyclodextrin (β-CD) epichlorohydrin (ECH) copolymer (β-CDEP) can extract non-ionized aromatic compounds quantitatively from aqueous samples. The polymer used is a colorless, transparent and insoluble solid with a maximum capacity of 0.82 μmol aromatic compounds per gram. It was synthesized by co-polymerization of β-CD and ECH and characterized by FT-IR and UV. β-CDEP does not contain double bonds, and therefore it does not have appreciable absorbance in the UV region. The optimum pH range for the extraction of aromatic compounds is 2.5-5.0. The method has high extraction efficiency with the recoveries between 90 and 101% for aromatic compounds at 0.02-1.67 ppm levels, and the analytes can be easily eluted by methanol washing after preconcentration.     

有机溶剂/缓冲液两相体系中全细胞催化拆分环氧氯丙烷

研究了有机溶剂/缓冲液两相体系中重组大肠杆菌E.coli BL21 (DE3)全细胞水解动力学拆分外消旋环氧氯丙烷制备(R)-环氧氯丙烷的过程.结果表明,最适反应条件为:最适有机溶剂异辛烷与缓冲液的体积比7:3,最适缓冲液pH 8.0,底物浓度574mmol/L,全细胞加入量0.07g湿菌体/ml溶液,温度30℃.在此条件下于1L反应器中反应45min,(R)-环氧氯丙烷的摩尔产率、光学纯度和时空产率分别达到37.5%,99.3%ee和0.286mol/(L·h).与单一水相体系相比,异辛烷/缓冲液两相体系中底物浓度和(R)-环氧氯丙烷时空产率分别提高了55.2%和98.6%.     

Synthesis of Lanthanide–Alkylaluminium Bimetallic Complexes and Studies on Their Catalytic Activities for Polymerization of Some Polar Monomers

Three new lanthanide (Ln)–alkylaluminium (Al) bimetallic complexes with the formula [(μ-CF₃CO₂)₂Ln(μ-CF₃CHO₂)AlR₂ · 2THF]₂ (Ln=Nd, Y, R=i-C₄H₉ (i-Bu); Ln=Eu, R=C₂H₅(Et); THF=tetrahydrofuran) were synthesized by the reaction of Ln(CF₃CO₂)₃ (Ln=Nd, Y) with HAl (i-Bu)₂ and of Eu(CF₃CO₂)₃ with AlEt₃, respectively. Their crystal structures were determined by X-ray diffraction at 233 K. [(μ-CF₃CO₂)₂Nd (μ-CF₃CHO₂)Al(i-Bu)₂ · 2THF]₂ (Nd–Al) and [(μ-CF₃CO₂)₂Y(μ-CF₃CHO₂)Al(i- Bu)₂ · 2THF]₂ (Y–Al) are isomorphous and crystallize in space group P 1 with a =12.441(3) Å [12.347(5) Å for Y–Al], b =12.832(3) Å [12.832(4) Å], c =11.334(3) Å [11.292(8) Å], α=104.93 (2)° [104.45(4)°], β=98.47(2)° [98.81(4)°], γ=64.60(2)° [64.30(3)°], R =0.519 [0.113], R _w=0.0532 [0.110], Z =1 and [(μ-CF₃CO₂)₂Eu(CF₃ CHO₂)AlEt₂ · 2THF]₂(Eu–Al) in space group P 2₁/ n with a =11.913(6) Å, b =14.051(9) Å, c =17.920(9) Å, α=101.88(11)°, β=γ=90°, R =0.0509, R _w=0.0471 and Z =2. The six CF₃CO     

C3手性合成子的合成及应用

简要介绍了两种重要的C3手性合成子———环氧氯丙烷(ECH)和缩水甘油(GLD)的合成方法;综述了ECH在药物合成以及GLD在部分有机合成中的应用。参考文献34篇。     

5-芳氧甲基-2-噁唑烷酮的合成及表征

环氧氯丙烷;氯甲基噁唑烷酮;合成;芳氧甲基噁唑烷酮     

Ti-MWW催化烯丙基氯环氧化高效合成环氧氯丙烷

 研究了具有MWW结构的新一代钛硅分子筛Ti-MWW催化剂对烯丙基氯液相环氧化高效合成环氧氯丙烷的催化性能. 结果表明, Ti-MWW的催化活性以及产物选择性均优于传统的钛硅分子筛TS-1. 对于Ti-MWW,合适的溶剂为非质子性溶剂丙酮和乙腈,在该溶剂中环氧化物不易发生溶剂化开环反应; 而对于TS-1,合适的溶剂是质子性溶剂甲醇,但甲醇可导致醇醚副产物的生成. 在Ti-MWW催化剂上烯丙基氯的转化率和环氧氯丙烷的选择性都能达到99%以上.