萘二磺酸钠转化产物催化合成双酚S及精制

采用阳离子交换树脂将2,6-萘二磺酸钠转化为2,6-萘二磺酸并用于双酚S(BPS)合成,研究了转化时间、温度、树脂用量等条件对反应的影响。较优的转化条件为:将2,6-萘二磺酸钠完全溶解后,加入用量为理论值37倍的001×7型强酸性聚苯乙烯系阳离子交换树脂,常温转化24 h,用转化产物催化合成的BPS粗品收率为93.5%,BPS质量分数为92.3%。采用水-吸附剂体系进行精制,不添加有机试剂,BPS产品质量分数高,操作简单,易于工业化。较优的精制条件为:7 g BPS粗品加热溶于300 g去离子水后,加入0.5 g海泡石、0.2 g活性炭,回流搅拌1 h,过滤后潮品再加热溶于180 g去离子水中,加入0.3 g海泡石,回流搅拌1 h,得白色产品,BPS质量分数可达99.7%。精制水可循环套用且可提高BPS产品收率至82.9%。     

超声波辅助下新型2,6-二-(苯并呋喃-2-甲酰基)吡啶衍生物的简便合成

报道了以2,6-二溴乙酰基吡啶为底物,在乙腈为溶剂、PEG-400为催化剂的条件下分别与水杨醛、取代水杨醛及2-羟基-1-萘醛利用超声波辅助的Rap-Stoermer反应合成2,6-二-(苯(萘)并呋喃-2-甲酰基)吡啶衍生物的简便方法.提供了一种将吡啶环和苯(萘)并呋喃环通过羰基联接构建成新型杂环骨架结构的新途径.该方法具有反应时间短、条件温和、收率良好的优点.产物结构经1H(13C)NMR,IR和元素分析表征.     

不同拓扑结构分子筛催化1-甲萘异构化-烷基转移耦合反应性能对比

以1-甲萘和均三甲苯为原料经固体酸催化的异构化-烷基转移耦合反应制备2-甲萘及二甲基萘。对MWW、BEA、FAU、MFI拓扑结构分子筛的催化性能进行对比研究,对反应机理进行探讨。采用XRD、BET、SEM、NH_3-TPD、PyFTIR及ICP等方法对催化剂结构物性进行了表征。与具有十元环特征孔道的MFI分子筛相比,具有十二元环特征孔道的MWW、BEA、FAU分子筛表现出更好的催化活性。BEA结构分子筛具有较高的二甲基萘选择性,而MWW结构分子筛具有较高的2-甲萘选择性并表现出优异的催化稳定性。在MWW结构分子筛中,HMCM-22的1-甲萘转化率达到70.27%,2-甲萘收率达到66.69%。而HMCM-56上则同时获得35.74%的2-甲萘收率和19.00%的二甲基萘收率。该研究为以中国丰富的碳十资源为原料制备高端聚酯单体2,6-二甲基萘开辟了颇具潜力的技术路线。     

用硅胶担载三氯化铁催化氧化偶联2-萘酚制备(±)2,2′-二羟基-1,1′-联萘

2,2′-二羟基 - 1 ,1′-联萘 ,由于存在受阻 C- C键轴 ,可通过拆分获得对映体纯手性双膦配体BINAP的前体 [1] ,或经不对称氧化转化成催化剂前体 [2 ] ,或用作手性试剂 ,近年来备受人们的重视 .其常用制备方法多以 Fe3 、 Mn3 及 Cu2 氧化 2 -萘酚 .尤以 Fe3 [3～ 5] 为氧化剂制备 (± ) 2 ,2′-二羟基 -1 ,1′-联萘最为经济 .传统上以甲醇 /水 ( 1 /1 ,体积比 )为介质 ,用 Fe Cl3 氧化 2 -萘酚制 (± ) 2 ,2′-二羟基 - 1 ,1′-联萘 ,产率不太高 [5] .近年来 ,Toda等 [5]利用固态反应及超声波制备此化合物 ,收率明显提高 ,但…     

化学液相沉积法改性HY沸石及其对萘与叔丁醇择形烷基化反应的催化性能

采用化学液相沉积法,经异丁基三乙氧基硅烷修饰并用高温水蒸气处理得到了改性HY沸石.采用X射线衍射、低温N2吸附和脉冲式质量分析技术研究了改性样品骨架结构、比表面积、孔结构参数和吸附性质的变化,并考察了HY沸石及其改性后样品对萘与叔丁醇烷基化制备2,6-二叔丁基萘(2,6-DTBN)反应的催化性能.结果表明,改性后HY沸石的骨架结构基本不变,但比表面积增大,平均孔径缩小,孔口尺寸得到了一定调变.在改性后HY沸石催化剂上萘与叔丁醇烷基化反应活性下降,但催化剂择形性能明显提高,其2,6-DTBN/2,7-DTBN比可以达到6.62。     

2,7-二甲氧基-3,6-二苯氧基萘的合成

以3,6-二溴-2,7-二羟基萘为起始原料,与硫酸二甲酯经甲醚化反应得3,6-二溴-2,7-二甲氧基萘(2);2与苯酚在碘化亚铜催化下经取代反应合成了新化合物——2,7-二甲氧基-3,6-二苯氧基萘,总收率82.5%,其结构经1H NMR,13C NMR,ESI-MS和元素分析表征。     

2—羟基—3,8—二甲氧基萘的甲酰化

为合成2-羟基-3、8-二甲氧基萘醛(Ⅰ),选用2-羟基-3、8-二甲氧基萘(Ⅱ))为原料,试以Gattermann-Adams法,及Duff反应进     

新型沙美特罗衍生物的合成

以沙美特罗的缩酮保护产物为原料,经长链仲氨的叔丁氧羰基保护、分子内酯交换反应选择性保护氨基间位的苄羟基、脱缩酮保护、与昔萘酸甲酯的Friedel-Crafts反应后再经碱水解合成了一个新型的沙美特罗衍生物——1-羟基-4-【2-羟基-5-【1-羟基-2-{[6-(4-苯丁氧基)]己氨基}乙基】苯甲基】-2-萘甲酸,总收率16.3%,其结构经1H NMR和MS表征。     

2个含呫吨结构双酚化合物的合成

以呫吨酮为原料,经二氯亚砜氯化得到9,9-二氯呫吨中间体,无需分离纯化,将其分别与邻甲酚和2,6-二甲基苯酚进行取代反应,制得2个含呫吨结构的双酚化合物9,9-二(4-羟基-3-甲基苯基)呫吨和9,9-二(4-羟基-3,5-二甲基苯基) 呫吨,产率分别为81.0%和80.5%。 用FTIR、1H NMR、13C NMR和元素分析对其组成和结构进行了表征。 该法具有操作简单、反应条件温和及收率高等优点。     

2,6-二甲酰基对甲苯酚的固相合成

以活性纳米γ-MnO2为氧化剂,在无溶剂状态下用2,6-二甲羟基对甲苯酚为原料合成了2,6-二甲酰基对甲苯酚,其结构经^1H NMR,IR和元素分析确证。较适宜的反应条件为：2,6-二甲羟基对甲苯酚0．85g(5mmol),n(2,6-二甲羟基对甲苯酚)：n(活性γ-MnO2)=1：2,间歇性研磨提供充分的自扩散时间(1h～2h),总研磨时间为5h～6h,收率26％。该法与液相合成法相比,反应时间缩短到1／8,产率提高了6％。     

碱性水溶液中单6-氧-对甲苯磺酰-β-环糊精酯的非均相合成

不引入有机溶剂,低温下将对甲苯磺酰氯与β-环糊精在NaOH水溶液中进行非均相反应,得到了单6-氧-对甲苯磺酰-β-环糊精酯(6-OTs-β-CD).借助1H NMR谱证实了环糊精单磺酰化机理.考察了产物的水解因素,研究了反应条件对产率的影响.实验结果表明,投料摩尔比n(CD)∶n(TsCl) =4∶1,碱液浓度0.75...     

The optimization of silica gel synthesis from chemical bottle waste using response surface methodology

To reduce the amount of hazardous chemical bottle waste in the environment, we report the optimization research of silica extraction in chemical bottle waste into silica gel. Alkali fusion and sol–gel process were utilised to prepare silica gel effectively. The alkali fusion process was carried out by adding sodium hydroxide to produce sodium silicate. Afterwards, silica gel was prepared by the sol–gel method using hydrochloric acid. Box-Behnken Design (BBD) was applied to Optimisation factors the poptimiseactors affecting the silica recovery. The factors that optimised mass ratio, particle size, and temperature. The optimum recovery of silica gel was obtained by SiO₂: NaOH mass ratio of 1:3, the particle size of 63–74 µm, and a temperature of 800 °C. The purity of silica gel optimum is 63.74% characterised using X-ray fluorescence. The structure of silica gel is the appearance of amorphous peaks at 2θ 20-30° characterised using an x-ray diffractogram. The silica gel surface was characterises using scanning electron microscopy-energy dispersive x-ray. It showed an irregular surface and characteristic showed that silica gel had a radius of 15.74 nm and a specific surface area of 297.08 m².     

A new synthesis of symmetrical 2,5-diaryl-1,3,4-thiadiazoles

Treatment of aromatic aldehydes with sulfur and hydrazine hydrate in the ratio 1:2:3, respectively, under the Willgerodt conditions affords the title compounds in excellent yields and in a good state of purity. Under the same conditions 2-chloro and 2,6-dichlorobenzaldehyde yield 3H-1,2-benzodithiole-3-thione and bis-(2,6-dichlorobenzyl)tetrasulfide, respectively.     

Regioselective oxidative polymerization of 1,5-dihydroxynaphthalene catalyzed by bilirubin oxidase in a water–organic solvent mixed solution

Bilirubin oxidase (EC1.11.1.7) was used to catalyze the oxidative polymerization of 1,5-dihydroxynaphthalene to its polymer in a mixed solvent composed of dioxane, ethyl acetate, and acetate buffer. In an aqueous solution, the enzymatic oxidative polymerization hardly occurred and resulted in negligible yield mainly due to the poor solubility of 1,5-dihydroxynaphthalene. In the mixed solvent the conversion proceeded with a yield of ca. 70%. The polymer yield was studied with respect to reaction time and solvent components. Elemental analysis, UV-visible, fluorescent, and FT-IR spectroscopic analyses, proton NMR and electrochemical studies, and solubility in various organic solvents revealed that 1,5-dihydroxynaphthalene is polymerized by the C? C coupling. The molecular weight of the polymeric products solubilized with DMF varied from low molecular weight product to high molecular weight polymer. From the chromatographic studies, the organic solvent–insoluble residue was suggested to be highly polymerized material. Based on these findings a possible mechanism for enzymatic polymerization of 1,5-dihydroxynaphthalene is presented: less stable intermediates produced enzymatically from 1,5-dihydroxynaphthalene undergo coupling and polymerization to ortho-1,5-dihydroxynaphthalene polymer, thereby resulting in a regioselective polymerization of 1,5-dihydroxynaphthalene. © 1993 John Wiley & Sons, Inc.     

Organic anion recognition of naphthalenesulfonates by steroid-modified beta-cyclodextrins: enhanced molecular binding ability and molecular selectivity

Two beta-cyclodextrin (beta-CD) derivatives bearing steroid groups (1 and 2) were synthesized by the condensation of mono(6-aminoethylamino-6-deoxy)-beta-CD with cholic acid and deoxycholic acid, respectively, and their original conformations and binding behavior to the organic anion of naphthalenesulfonate derivatives were investigated by using 1H NMR spectroscopy and spectrofluorometric titration in combination with computational methods. The 2D NMR experiments reveal that the steroid groups attached to the beta-CD rim could be deeply embedded in the beta-CD cavity to form the intramolecular (for 1) or intermolecular (for 2) inclusion complexes in aqueous solution. Upon complexation with naphthalenesulfonate derivatives, modified beta-CDs display two obviously different binding modes, that is, the competitive inclusion mode and the induced-fit inclusion mode, which is consistent with the results of molecular modeling study. The two modes and the strict size/shape fitting relationship between the hosts and guests reasonably explain the different binding behaviors and molecular selectivity of host beta-CDs 1 and 2 toward the naphthalenesulfonate guests. Therefore, the cholic acid- or deoxycholic acid-modified beta-CDs could effectively recognize the size/shape of guest molecules as compared with the parent beta-CD, giving good molecular selectivity up to 24.9 for the disodium 2,6-naphthalenedisulfonate/disodium 1,5-naphthalenedisulfonate pair by the host 1.     

2-吲哚酮和5-甲基-2-吲哚酮的无溶剂法制备

以苯胺和氯乙酰氯为原料在NaOH存在下酰化合成N-氯乙酰基苯胺,然后N-氯乙酰基苯胺在无水AICI,催化下环化合成2-吲哚酮．对由N-氯乙酰基苯胺合成2-吲哚酮的工艺条件进行了改进．结果表明合成2-吲哚酮的最佳条件为：反应温度为220℃,反应时间为60min,加料时温度为180℃,N-氯乙酰基苯胺与氯化钠,无水AlCl3的重量比为1：1：5．5．改进后的合成2-吲哚酮收率达到88．3％,纯度99％,收率比原工艺提高了24．6％．在此基础上,还合成了5-甲基-2-吲哚酮,并得到其最佳条件为：反应温度为190℃,反应时间为30min,加料时温度为180℃,4-甲基-N-氯乙酰基苯胺与氯化钠,无水AlCl3的重量比为1：1：5．5,收率达到83．1％,纯度为99％．     

六苯氧基环三磷腈的合成及其在层压板中的阻燃应用

以六氯环三磷腈（HCCTP）粗产物、苯酚、NaOH为反应原料,四丁基氯化铵（TBAC）为相转移催化剂,氯苯和水为溶剂,合成了六苯氧基环三磷腈（HPCTP）,考察了反应温度、反应时间、反应溶剂、物料配比对收率的影响。结果表明,在最佳原料配比n(NaOH): n(苯酚): n(TBAC): n(HCCTP粗产物)=7.5: 6.3: 0.15: 1,30 ℃反应4 h,回流反应6 h,HPCTP的收率达到75％。采用红外光谱、核磁氢谱、碳谱、磷谱、X射线衍射分析、示差扫描量热分析、热重分析测试技术对产物进行了表征分析,并首次用于苯并噁嗪树脂玻璃布层压板,当HPCTP的质量分数为10％时,燃烧等级达到V-0级,平行击穿电压为47 kV,热态弯曲强度为596 MPa。     

A convenient method for the synthesis of roflumilast

A convenient synthetic method has been developed for the synthesis of roflumilast from 4-difluoromethoxy-3-hydroxybenzaldehyde and bromomethyl cyclopropane via O-alkylation, oxidation and N-acylation. With sodium hydroxide as alkali in the last step, the total yield of roflumilast can be up to 68.3 % and the purity of the target product reached 99.2 %. It was obvious that sodium hydroxide showed more economic advantage for scale-up production than sodium hydride or potassium tert-butoxide.     

Protonation effects on the inclusion complexation of 6-deoxy-6-diethylamino-beta-cyclodextrin with 2-anthracenesulfonate, 2-naphthalenesulfonate, 2,6-naphthalenedisulfonate, and 2,7-naphthalenedisulfonate in aqueous solutions

At pH values 5.5 and 10.3, 6-deoxy-6-diethylamino-beta-cyclodextrin (DD-beta-CD) as well as beta-CD forms 1:1 inclusion complexes with 2-anthracenesulfonate (2AS), 2-naphthalenesulfonate (2NS), 2,6-naphthalenedisulfonate (2,6NDS), and 2,7-naphthalenedisulfonate (2,7NDS). The equilibrium constants (K) for the formation of the 1:1 inclusion complexes have been evaluated from the absorbance and/or fluorescence intensity changes. With respect to the beta-CD inclusion complexes of 2AS, 2NS, 2,6NDS, and 2,7NDS, the K values at pH 5.5 are nearly the same as the corresponding ones at pH 10.3. In the case of the DD-beta-CD inclusion complexes, the K values of 2AS and 2NS similarly do not depend on the pH value. However, the K values of 2,6NDS and 2,7NDS for DD-beta-CD at pH 5.5 have been found to be more than two times greater than the corresponding ones at pH 10.3, suggesting the electrostatic attraction between the protonated diethylamino group of DD-beta-CD and the sulfonato group of the NDSs.