PREPARATION OF POLY（METHYL METHACRYLATE）/LAYERED DOUBLE HYDROXIDES NANOCOMPOSITES via in situ SOLUTION POLYMERIZATION

An exfoliated layered double hydroxides/poly(methyl methacrylate)(LDHs/PMMA)nanocomposite was prepared by in situ solution polymerization of methyl methacrylate(MMA)in the presence of 4-vinylbenzenesulfonate intercalated LDHs(MgAl-VBS LDHs).MgAl-VBS LDHs was prepared by the ion exchange method,and the structure and composition of the MgA1-VBS LDHs were determined by X-ray diffraction(XRD),infrared spectroscopy and elemental analysis.XRD and transmission electron microscopy(TEM)were employed to examine the structure of LDHs/PMMA nanocomposite.It was indicated that the LDHs layers were well exfoliated and dispersed in the PMMA matrix.The grafting of PMMA onto LDHs was confirmed by the extraction result and the weight fraction of grafted PMMA increased as the weight fraction of LDHs in the nanocomposites increased.     

1,3-手性转移反应的研究 (4R)-和(4S)-4-甲基(E)-2-辛烯醇的合成

以手性辛烯二醇双酯与甲基锂铜反应, 经1,3手性转移, 分别生成立体选择性高的(4R)和(4S)-4-甲基-辛烯醇酯。     

青蒿素及其一类物的结构和合成XVI.青蒿戊素的合成和α-环氧青蒿酸甲酯环氧的开环反应

β-环氧青蒿酸甲酯(25)经甲酸处理得反式双竖键开环产物(26),经水解和内酯化得青蒿戊素(1),α-环氧青蒿酸甲酯(5)或叔丁酯(18)及α-环氧双氢青蒿酸甲酯(12a,b)与甲酸反应未生成反式双竖键开环产物,并对其反应机理作了讨论。     

(±)胡枝子黄烷酮-A的全合成

胡枝子黄烷酮-A为6,8-二(γ,γ-二甲基烯丙基)-4'-甲氧基-5,7,2'-三羟基(2S)-黄烷酮(1)。本文报道了其外消旋体的全合成。     

6α-取代的(1S, 7aS)-(+)-1-叔丁氧基-7a-甲基-2, 3, 5, 6, 7, 7a-六氢茚-5- 酮的合成

用化学动力学控制的方法在化合物3的5-C上C=O与6-C发生烯醇化生成锂盐,然后可在6-C位分别引入甲基、烯丙基、苄基、溴以及羟基取代基。产物6、7、8、9a和11经鉴定,除9α外其他都是α和β构型的混合物,其中以α-构型取代物为主。     

Methyl orange adsorption by microporous and mesoporous TiO2-SiO2 and TiO2-SiO2-Al2O3 composite xerogels

We investigate the adsorption behavior of methyl orange (MO) on composite xerogels. Mesoporous TiO₂-SiO₂ and TiO₂-SiO₂-Al₂O₃ xerogels are prepared by hydrolysis of tetraethyl orthosilicate (TEOS), tetrabutyl orthotitanate (TBOT), and AlCl₃ ·6H₂O using HCl as a catalyst and cetyltrimethylammonium bromide (CTAB) as a templating agent. The corresponding microporous xerogels are also prepared without addition of CTAB. These xerogels are then characterized by XRD, FTIR, and BET.We find that MO is adsorbed by the mesoporous xerogels in acidic solutions, showing Langmuir type adsorption isotherms. We also find that the adsorption decreases with increasing temperature. It is suggested that adsorption exhibits a sieve effect and that MO is adsorbed through electrostatic attraction and hydrogen bonding between MO and the xerogels.     

甾体植物生长促进剂的研究 VIII: 3α-羟基-7-氧-6-酮-B-高-5α-胆烷酸甲酯的区域选择性合成

油菜甾醇是以油菜花粉分离到的一种促进植物生长甾体, 能促进细胞生长和分裂,与已知植物生长的元素相比, 它具有广谱生物活性, 因此他可能在农业上有实际应用的价值.本文报道了3α-羟基-7-氧-6-酮-B-高-5α-胆烷酸甲酯的区域选择性合成.     

中药白术的化学成分 II: 白术三醇的α-甲基丁酰衍生物

本文从中药白术中分离出四种白术三醇的α-甲基丁酸酯化合物, 并运用质谱分析方法和化学实验方法确定了它们的结构, 它们是: 12-α-甲基丁酰-14-乙酰-8-顺式-白术三醇(1), 12-α-甲基丁酰-14-乙酰-8-反式-白术三醇(2), 14-α-甲基丁酰-8-顺式-白术三醇(3)、14-α-甲基丁酰-8-反式-白术三醇(4)。     

O-甲基己内酰亚胺和N-甲基己内酰胺的波谱分析

1948年Benson等将己内酰胺(1)和硫酸二甲酯在不同条件下反应,得到两个异构的甲基化产物.他们根据产物的反应性能指定一个产物为O-甲基己内酰亚胺(2),另一个产物为N-甲基已内酰胺(3).作者应用~1H NMR进一步证实了Benson等所推断的这两个化合物的结构.2和3的波谱数据只见过零星报道,且未作对比解析.本文除了探讨1和硫酸二甲酯的摩尔配比是否是反应生成2或3的主要因素外,还测定了2和3的紫外光谱、红外光谱、核磁共振谱及质谱.     

六次甲基四胺与溴代丙烯加合物的晶体结构

我们对六次甲基四胺(HMT)加合物的研究早感兴趣。为探讨Sommelet反应机理,我们证实氯化苄与HMT加合物为季胺盐阳离子[(CH_2)_6N_4·CH_2C_6H_5]~ 与Cl~-交错堆积组成的离子晶体。晶体中与四配位N联结的C-N键长有明显的增长效应。本文为其平行的工作。实验HMT与溴代丙烯加合物晶体的制备0.8g HMT溶于30 mL 1∶1三氯甲烷-丙酮,滴入0.7mL溴丙烯,待有细小晶体析