Mesostructured Sulfated Tin Oxide and its High Catalytic Activity in Esterification and Friedel–Crafts Acylation

A mesostructured sulfated tin oxide with large surface area (172 m²/g) has been successfully prepared using a block copolymer as structure-directing agent, which is extensively characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), nitrogen adsorption, and Thermogravimetric analysis (TG) techniques. The results indicate that the mesostructured sulfated tin oxide was tetragonal crystalline, and catalytic tests show that the mesostructured sulfated tin oxide is much more active than conventional one for esterification and Friedel–Crafts acylation.     

[Emim]Br-FeCl_3催化合成二苯甲酮的活性与酸性的关联

以功能化酸性离子液体[Emim]Br-FeCl3为催化剂,苯和苯甲酰氯为原料酰基化合成二苯甲酮,考察了离子液体的路易斯酸强度对催化活性的影响,并对离子液体的酸强度进行了红外表征。结果表明：FeCl3含量越高,离子液体的酸强度越大,二苯甲酮催化反应活性越高,强酸位有利于该酰基化反应的进行。X=0.75时催化活性最好,达98.3%。     

Reactions of free chlorine with substituted anilines in aqueous solution and on granular activated carbon

Aqueous HOCl reacted with substituted anilines to form chlorinated derivatives. Some debromination and bromination products were also detected from two brominated anilines. When granular activated carbon was present, many additional products were formed. These compounds fall into several different groups: (1) N-acylation products, (2) N-carbomethoxylation products, (3) N=N dimerization products and (4) deamination and hydroxylation products.     

DL-丝氨酸乙酰化合成的研究

光学活性丝氨酸具有特殊的生理功能,在食品、医药领域具有广阔的应用前景,目前尚未国产化,其研究开发日益受到人们的重视.化学合成的N-氯乙酰基-DL-丝氨酸经固定化酶拆分成L-丝氨酸和D-丝氨酸.探讨了DL-丝氨酸的乙酰化方案并进行了乙酰化实验,确定了以氯乙酰氯为酰化剂酰化实验工艺参数,包括pH、反应物配比、反应温度等.     

2-甲氧基-6-酰基萘的合成研究

以２ 萘酚为原料,通过甲基化、酰基化合成２ 甲氧基 ６ 酰基萘。探讨了温度、溶剂、投料比和反应时间对收率的影响。     

High Atom Efficiency in Sc(OTf)3‐Catalyzed Allylation of Aldehydes with Tetraallyltin

The high atom efficiency was achieved through addition of Ac₂O in the Sc(OTf)₃‐catalyzed allylation of aldehyde with tetraallytin in a 4 : 1 molar ratio.     

Antimony(V) Chloride‐Benzyltriethylammonium Chloride Complex as an Efficient Catalyst for Friedel−Crafts Acylation Reactions

A novel catalytic system, the complex of antimony(V) chloride (SbCl₅) and benzyltriethylammonium chloride (TEBA), C₆H₅CH₂NEt₃(SbCl₅)₂Cl complex, is described for Friedel–Crafts acylation reactions of aromatics with acyl and sulfonyl chlorides. The catalyst has a number of useful characteristics, such as ready access, minimal toxicity, reusability, insensitivity to atmosphere and moisture, rapid acylation with high yield, and ease of operation.     

Absorption of metal cations by modified B. mori silk and preparation of fabrics with antimicrobial activity

Silk fabrics were modified by treatment with tannic acid (TA) solution or by acylation with ethylenediaminetetraacetic (EDTA) dianhydride. Kinetics of modification with TA and acylation with EDTA–dianhydride was investigated. The physico‐mechanical properties of silk fabrics acylated with EDTA–dianhydride remained unchanged regardless of chemical modification. The absorption of metal cations (Ag⁺, Cu²⁺) by untreated and modified silk fabrics was studied as a function of the kind of modifying agent, weight gain, and pH of the metal solution. The absorption of Cu²⁺ at alkaline pH was not significantly influenced by chemical modification of the silk substrate. The absorption of Ag⁺ by acylated silk remained at a level as low as untreated silk, while was enhanced by TA. The higher the content of TA, the higher the absorption of Ag⁺. With respect to the pH of the metal solution, the acylation with EDTA–dianhydride enabled silk to absorb and bind metal cations even in the acidic and neutral pH range, where tannic acid had no effect. Medium to high levels of metal desorption were exhibited by untreated and modified silk fabrics towards the metal cations, with the only exception of the silk–tannic acid–Ag complex, which displayed an extraordinary stability. All metal‐containing silks exhibited significant antibacterial activity. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 297–303, 2001