CATALYSIS OF POLYSTYRENE N-HYDROXYL SULFONAMIDE FOR ESTERIFICATION OF BUTANOL WITH ACETIC ANHYDRIDE

Polystyrene N-hydroxyl sulfonamide resin l was prepared and used to catalyze the esterification of n-butanol and acetic anhydride. The mechanism of catalytic esterification proved by IR spectra of the resins was found that O-H and N-H of the N-lrydroxyl sulfonamide resin reacted with the acetic anhydride respectively to form the active intermediate polystyrene N.O-diaceyl sulfonamate which was cleaved by n-butanol to produce butyl acetate. The catalytic esterification by resin I was in good agreement with the kinetic model of “bi-bi-ping-pong“ mechanism.     

聚苯乙烯磺酰氯与三氯化铁复合物的合成及其对乙酸和正丁醇酯化反应的催化作用

聚苯乙烯磺酰氯树脂１与三氯化铁或三氯化铁的六水合物在二氯乙烷的回流温度下分别制得了复合树脂２和复合树脂３。这两种树脂在二氯乙烷中分别用无水ＨＣＬ处理分别得到复合树脂４和复合树脂５。用对硝基氯苯作指示剂测得复合树脂２的Ｈａｍｍｅｔｔ酸度常数为－１２．７０。这些树脂在６０℃下催化乙酸和丁醇（摩尔比为１：１３）的酯化反应中虽然树脂３没有明显的催化活性，但其余三种复合树脂的催化活性是其母体聚苯乙烯磺酰氯树脂的３～４倍，是强酸树脂催化剂Ｄ７２的４～６倍。     

稀土盐酯化催化剂失活原因的探讨

实验发现，稀土盐作为酯化反应催化剂，重复使用时活性有较大幅度的下降。本文采用Ｘ射线衍射（ＸＲＤ）及程度升温分解（ＴＰＤＥ）等手段，结合四水硫酸铈（Ⅳ）催化合成乙醇单乙醚醋酸酯的反应活性测定，对鹇催化剂和经不同预处理的催化剂进行了研究，讨论了催化剂失活的原因。结果表明，四水硫酸铈（Ⅳ）的催化活性与表面质子酸性质有关。在反应过程中，催化剂发生结晶水的丢失，铈离子价态的降低及晶体结构的变化，使催化剂的质     

层柱状粘土催化合成乙二醇单烷基醚乙酸酯

为了克服均相催化剂在用于制备各种重要化学品的一些困难,层柱粘土催化剂在活性、选择性,重复使用性及经济方面已经证明是非常有利的。由活性白土经硫酸和铝盐进行处理,然后在１００￣４００℃焙烧制得了催化剂,考察了醇醚与乙酸的酯化活性并对催化剂进行了表征。     

SYNTESIS OF THE COMPLEXES OF MACROPOROUS SULFONATED RESINS WITH FERRIC CHLORIDE AND THEIR CATALYTIC BEHAVIOR FOR SETERIFICATION OF ACETIC ACID WITH BUTANOL

The complex resins prepared from macroporous sulfonated resin D72(H^+ form) with ferric chloride or ferric chloride hexahydrate have both sites of Bronsted acid and Lewis acid.In the catalysis of exterification of acetic acid with butanol the complex resins show to have much higher catalytic activity than that of its matrix.a conventional sulfonated cation exchange resin D72.     

用钨磷杂多酸作催化剂合成己酸乙酯的研究

用钨磷杂多酸作催化剂合成己酸乙酯的研究卓润生，田来进（曲阜师范大学化学系，曲阜，２７３１６５）周世新（石油大学炼制系东营２５７０６２）关键词酯化反应，杂多酸，己酸乙酯己酸乙酯作为一种香料广泛用于食品工业。目前工业上均用硫酸作催化剂．以乙醇和正己酸为原...     

A NOVEL COPOLYMER-BOUND CIS-DICARBONYLRHODIUM COMPLEX FOR THE CARBONYLATION OF METHANOL TO ACETIC ACID AND ACETIC ANHYDRIDE

A series of porous microspheres of linear and ethylene diacrylate (M') cross-linked copolymers of 2-vinylpyridine (V) and methyl acrylate (M) reacted with tetracarbonyldichlorodirhodium to form a series of cis-dicarbonylrhodium chelate complex (MVRh and MVM 'Rh). They are thermally stable yet very reactive in the carbonylation of methanol to acetic acid, and of methanol-acetic acid mixture to acetic acid and acetic anhydride with a selectivity of 100% under relatively mild and anhydrous conditions.     

聚苯乙烯单分散微球粒径可控性探讨

在系统研究分散聚合反应中的原料组成(分散稳定剂、单体、引发剂)和反应条件(反应介质极性、反应体系温度、搅拌速度)对所制备的聚合物微球的粒径大小及粒径分布和聚合反应速率影响的基础上,根据各因素的影响效应,优化设计分散聚合的反应条件,成功地制备出1μm~10μm粒径范围内不同粒径级别的微米级单分散聚合物微球,实现了不同粒径大小及粒径分布的微米级单分散聚合物微球制备的控制设计。     

STUDY OF THE MECHANISM FOR THE REARRANGEMENT OF THIOLSULFINATE WITH ACETIC ANHYDRIDE BY 13C AND 18O-TRACER EXPERIMENTS

Abstract

Recently, we found that benzyl phenylmethanethiolsulfinate (I) reacts with acetic anhydride at 60°C to afford the rearranged sulfoxide, i.e., an almost 1:1 mixture of both erythro and threo-1-(acetoxylthio)benzyl benzyl sulfoxides(II) in a substantial yield.     

聚苯乙烯大单体与丙烯酸酯接枝共聚物对聚苯乙烯表面的改性研究

研究了由大单体技术合成的侧链为聚苯乙烯、骨架由丙烯酸丁酯或甲基丙烯酸羟乙酯/丙烯酸丁酯组成的接枝共聚物对聚苯乙烯的表面改性效果(试样浇注于玻璃纸上成膜)。发现仅添加0.5wt％的接枝共聚物就可完全改变聚苯乙烯膜两面的临界表面张力γ-c与表面能中的色散力部份γ_s~D,少量添加的接枝共聚物在改性聚苯乙烯膜的两面呈现出明显的表面富集现象。虽然两类接枝共聚物的极性有较大的差异,但改性聚苯乙烯成膜后的自由表面均显示出与聚丙烯酸丁酯相同的低表面能(γ_s~D=37×10~(-3)牛顿·米~(-1)),而添加三元接枝共聚物的改性膜与玻璃纸接触的表面却具有高于聚苯乙烯的表面能|(γ_s~D=54×10(-3)牛顿·米~(-1))。这种改性膜的两面具有不同的表面能是由于接枝共聚物中不同的组分在膜的两面富集所致,已通过ESCA的表面测试结果证实,并与按Gibbs吸附式的计算值相符。     

乙酸甲酯羰化合成乙酐的镍催化剂的性能

乙酸甲酯羰化合成乙酐的镍催化剂的性能龚军芳蒋大智李小宝田世忠王恩来（中国科学院化学研究所，北京１０００８０）关键词羰基合成，镍催化剂，乙酸甲酯，乙酐，配体分类号Ｏ６４３／ＴＱ４２乙酸和乙酐的羰基合成新工艺标志着化工原料由石油向煤和天然气的首次重大转...     

A PETERSON OLEFINATION REACTION USING SILYL-SUBSTITUTED SULFONAMIDE CARBANIONS. SYNTHESIS OF VINYLIC SULFONAMIDES

Abstract

α-Trimethylsilyl-substituted sulfonamides RCH(SiMe₃)SO₂N(CH₃)₂ (3), (R[dbnd]H, CH₃ and C₆H₅) are synthetized in almost quantitative yields. Their lithium derivatives 4 undergo a smooth Peterson olefination reaction with nonenolisable carbonyl compounds to give good to excellent yields of vinylsulfonamides 6. With R[dbnd]H, the reaction is highly E-stereoselective. Moderate stereoselectivity is obtained in the cases of R[dbnd]CH₃ and R[dbnd]C₆H₅.     

头孢菌素酸的酯化引起其α,β双键移位的研究

本文采用各种方法合成若干噻孢霉素酯,并用~1H核磁共振谱测定其双键移位的比例。实验表明有机碱与极性溶剂都会促进双键移位。最后讨论了可能的机理。     

固相多肽合成中王树脂和Fmoc/tBu酪氨酸成酯反应的研究

以Fmoc/tBu酪氨酸和王树脂为原料,分别探讨了对称酸酐法、活化酯法和2,6-二氯苯甲酰氯(DCB)法中各种因素对氨基酸与树脂成酯反应的影响。实验表明:对称酸酐法连接率低,而其它两种方法,通过筛选合适的反应介质,均能取得良好结果。在活化酯法中,使用强极性溶剂DMA,弱极性溶剂THF/DCM和混合溶剂45%DMF/THF,反应5h,连接率均可提高到90%以上;在DCB法中,使用弱极性溶剂THF时,反应3h,连接率可达99%。总之,DCB方法是酪氨酸和王树脂成酯反应的最好方法。     

苯酰化聚苯醚/聚苯乙烯共混物相容性研究

采用DSC方法研究了聚苯乙烯(PS)和苯甲酰化聚苯醚(APPO)共混体系的相容性.相容共混体系Gordon-Taylor方程K参数随苯甲酰化程度(取代度)增加而变小,其玻璃化转变区随取代度增加而变宽,取代度大于76mol％时,共混物呈现双玻璃化转变.APPO/PS共混体系热诱导相图同时存在LCST和UCST现象,且相行为是可逆的.     

新型固体酸SO_4~(2-)/Fe_2O~3-ZrO_2-SiO_2的研制及其对乙酸/丁醇酯化反应酸催化作用的优化(英文)

采用共沉淀法与浸渍法制备了一系列ＳＯ４２－／Ｆｅ２Ｏ３－ＺｒＯ２－ＳｉＯ２固体酸催化剂,并将其用于催化乙酸／丁醉酯化反应。考察了以下影响催化剂活性的因素：Ｆｅ／Ｚｒ比、Ｓｉ含量、制备方法、预焙烧温度和焙烧温度等。催化剂采用如下条件制备： Ｓｉ含量为２ ％, Ｆｅ／Ｚｒ比为 ０．２５,共沉淀法, ７７３ Ｋ焙烧,此时酯收率及生成酯的选择性可分别达到９３.２６％和９６.０１％。 ＳＯ４２可能是活性组分之一。     

3－硝基－4－溴－1，8－萘二甲酸酐与己胺的反应

３－硝基－４－溴－１，８－萘二甲酸酐与己胺的反应柳波沈永嘉＊董黎芬（华东理工大学精细化工研究所，上海，２００２３７）关键词合成结构表征１，８－萘二甲酰亚胺１，８－萘二甲酰亚胺是一类良好的荧光发色体，其４位上有供电子基团的衍生物大都具有强烈的荧光，已被...     

PHOTOCHROMIC PROPERTIES OF (E)-DICYCLOPROPYLMETHYLENE-(2,5-DIMETHYL-3-FURYLETHYLIDENE)-SUCCINIC ANHYDRIDE DOPED IN POLYSTYRENE THIN FILMS

Fulgide 1-E doped in polystyrene polymer films was heated at various annealing temperatures.Upon irradiation with UV light(366 nm),fulgide 1-E undergoes a conrotatory ring closure to the pink colored closed form 1-C.The later color was switched back to the original color when the films were irradiated with white light.The kinetics of photocoloration and photobleaching processes were followed spectrophotometrically by monitoring the absorbance of the ring closed product 1-C at itsλ_(max) of 525 nm.The fir...     

REACTION OF (2-BENZOTHIAZOLYL)-SULFENAMIDES WITH P-CONTAINING REAGENTS

Abstract

The title reaction was investigated to find that only substitution reaction on amino group occurred when (2-benzothiazolyl)sulfenamides 1 reacted with P(NR₂,)₃, whereas the treatment of 1 with (RO)P(NR₂,)₂, gave derivatives of phosphorodiarnidothioic acid together with 2-alkylthiobenzothiazole and its isomer in addition to substitution products, and no substitution products obtained when N-substituted analogues of 1 were treated similarly.