环丁烯砜均相加氢制环丁砜的动力学研究

环丁砜是一种热稳定性高、毒性小、选择性高和溶解力强的高效芳烃抽提剂,同时也广泛用于天然气脱硫、纺织印染等方面.目前国内只有锦州炼油厂生产,他们采用雷尼镍间歇加氢工艺,该工艺催化剂耗量大,生产成本高.新工艺采用过渡金属络合物催化剂进行均相加氢,可改善原工艺的操作条件.环丁烯砜均相加氢制环丁砜曾有专利报导,但有关动力学方面的研究尚未见报导.     

粉末化学镀法制备的NiB／TiO2非晶态合金催化剂对环丁烯砜加氢反应的催化性能

 采用诱导沉积法及粉末化学镀法分别制备了纯态NiB及负载型NiB／TiO2非晶态合金催化剂．用XRD，ICP，SEM，TEM和DSC等手段对催化剂的物性及TiO2载体与NiB非晶态合金之间的相互作用进行了表征，考察了非晶态合金的结构、组成、形貌和热稳定性，并将其用于环丁烯砜加氢反应中．结果表明，相对于NiB而言，NiB／TiO2催化剂具有优良的热稳定性和催化活性，这缘于NiB和TiO2载体之间的相互作用及载体的分散作用．     

非晶态合金催化剂NiB、NiB/TiO2的制备、表征及其环丁烯砜加氢催化活性的研究

分别采用化学还原法和浸渍还原法制备了系列NiB及NiB／TiO2非晶态合金催化剂，用XRD、ICP、SEM、SAED和DSC等技术对催化剂的物性进行了表征，并将其用于环丁烯砜加氢反应，研究了制备条件(镍硼摩尔比、滴加方式和金属离子浓度)对非晶态合金催化剂加氢活性的影响。结果表明，选择镍硼摩尔比为1：2，Ni^2 浓度为0．1mol／L，采用正滴加方式(将KBH4溶液滴加到Ni(NO3)2溶液中)所制得的NiB非晶态合金催化剂环丁烯砜加氢活性优于RaneyNi催化剂，对于NiB／TiO2负载型非晶态合金催化剂，镍的实际负载量达14．5％时，NiB／TiO2与NiB的环丁烯砜加氢催化活性相当。     

环丁烯酮化合物高效合成喹啉衍生物的应用研究

在酸催化作用下,成功实现了3-氨基-2-环丁烯酮开环重排一步合成喹啉类化合物,对反应溶剂、催化剂、温度、投料比等影响因素进行了考察,在优化反应条件下催化合成了一系列喹啉类化合物,获得了较好的产率.该合成方法具有反应温度低、产率高以及反应迅速等优点,为喹啉类衍生物的合成建立了一种简单有效的新方法.     

螺二邻二亚甲基噻吩和环二邻二亚甲基噻吩的合成

Errede等曾利用氢氧化邻甲基苄基三甲基铵的热解制得螺二邻二亚甲基苯、环二邻二亚甲基苯和聚邻二亚甲基苯。Winberg等人对噻吩的季铵碱的热解有所研究,但未能触及活泼的中间体2,3-二亚甲基-2,3-二氢化噻吩Ⅷ及其二聚体螺环化合物和环状化合物。     

β,β-二氯丁烯酮甲基上的反应

通过4,4-二氯-3-丁烯-2-酮的氯甲基化,Mannich反应和醇醛缩合制备了1,1,5-三氯-p-戊烯-3-酮(2),1,1-二氯-9-二乙胺基-1-戊烯-3-酮盐酸盐(3)和1,1-二氯-1,4-己二烯-3-酮(4).氯甲基化产品(2)与三乙胺在醚反应生成1,1-二氯-1,4-戊二烯-3-酮(6),在醇中生成1,1-二氯-5-乙氧基-1-戊烯-3-酮(6).与容易在室温中聚合.(2)和氨在醇中反应可得到环化产品N-(4-酮基-5H,6H-2-吡啶基)-3H,4H,5H-吡啶-2,4-二酮.     

萘甲腈和2,3-二甲基丁烯-2-光环加成反应:三氟醋酸的效应

在低转光解情况下,1-萘甲腈(1-NpCN)和2,3-二甲基丁烯-2(DMB)在环已烷或苯中的光环加成反应主要得到环丁烷3,但2-NpCN主要得到氨杂环丁烯6和少量的环丁烷5,三氟醋酸(TFA)量增加抑制1-NpCN和DMB的光环加成反应,表明TFA与基态及单激发态1-NpCN生成非光反应的复合物,它也淬灭^*(1-NpCN-DMB)激基复合物.在低浓度范围(0.1M以下)TFA加速2-NpCN和DMB光环加成反应,但在高浓度范围(大于0.1M)时又抑制反应.这些结果被解析如下:^*(2-NpCN-DMB)激基复合物和TFA反应增加5和6的得率,反之,是由于生成非光反应的基态复合物及淬灭单激发态2-NpCN.在非极性溶剂中二种单激发态萘甲腈生成TFA激基复合物的萤光与母体^*NpCN萤光区域几乎相同.     

微波辐射下合成5-芳亚甲基-2,3-二芳基-4-噻唑啉酮类化合物

在水介质中,以四丁基溴化铵(TBAB)作催化剂,微波辐射下使芳醛与4-噻唑啉酮反应合成一系列5-芳亚甲基-2,3-二芳基-4-噻唑啉酮类化合物.该反应具有反应时间短、产率高、环境友好、后处理简便等优点.所有化合物均经IR,MS,1H NMR和元素分析确定.同时用X射线衍射法测定了化合物4a的晶体结构.     

5-苯亚甲基-2,4-噻唑二酮的催化合成和紫外光谱的取代基效应

在KF -Al2 O3 负载型固体碱催化下 ,2 ,4-噻唑二酮 1和芳香醛 2a～ 2f发生缩合反应 ,高产率地合成了 5-苯亚甲基 2 ,4-噻唑二酮 3a～ 3f,测定了产物 3a～ 3f在 16种溶剂中的紫外光谱 ,其最大吸收频率与Hammett取化基常数存在良好的线性关系     

二乙基硅氧烷双苯并环丁烯的合成及其聚合物性能

利用硅氢加成反应,以4-乙烯基苯并环丁烯(4-VBCB)和1,1,3,3-四甲基-1,3-二氢二硅氧烷（TMHS）为原料,一步法合成了二乙基硅氧烷双苯并环丁烯（DES-bis-BCB）,并对以其为单体在热引发条件下生成的预聚体进行了结构表征。 利用原子力显微镜和热重分析对预聚体的成膜性能和热性能进行了分析。 结果显示,薄膜的均方根（RMS）糙度为0.53 nm,初始分解温度为390 ℃,表明二乙基硅氧烷双苯并环丁烯聚合物具有良好的成膜性能和优异的热稳定性能。     

Perhalogenated thiazoles. Their synthesis,reactions and mass spectra

The synthesis of six new mixed perhalogenaled thiazoles ane reported. Three of these contain a 2-fluoro substituent one of which includes the novel 5-bromo-4-chloro-2-fluorothiazole. The mass spectral fragmentation pattern of the perhalogenated thiazoles was used to elucidate the orientation of the halogen suhstituents. A novel halogen migration from carbon to nitrogen in the mass spectrum was observed for several of the perhalogenated thiazoles. Nucleophilie displacement of fluoride ion in 4,5-diehloro-2-flurothiazile ( 7 ) by cyano, hydroxyl and methoxyl unions and by diclhyl amine produced the respective 2-substituted dichlorothiazoles. The ease of electrophilic substitution on carbon in the polyhalogenated thiazoles was observed to be 2 > > 5 > 4. Sulfur tetrafluoride fluorinalion of 2-earboxy-4,5-dichlorothiazole, formed by lilhiation and eurbonation of tricblorolhiazole, yielded 4,5-dicbloro-2-trifluoromethylthiazole.     

高分子负载苯并噻唑 盐的制备及其催化反应

制备了载于交联聚苯乙烯和苯乙烯与甲基丙烯酸羟乙酯的共聚物的苯并噻唑盐, 并研究了用这些高分子载体苯并噻唑盐催化的醛对α,β-不饱和化合物的Michael加成反应.     

Catalytic reactions of formate. 3. Noble metal chlorides as catalyst precursors for formic acid reactions

Summary Noble metal chlorides (RuCl₃·xH₂O, RhCl₃·3H₂O, PdCl₂ and IrCl₃·xH₂O) have been evaluated as catalyst precursors for the decomposition (HCO₂H H₂ + CO₂), dehydration (HCO₂H H₂O + CO) and air oxidation (2HCO₂H + O₂ 2H₂O + 2CO₂) of 88% HCO₂H at 75–80 °C. RhCl₃ under these conditions is an active oxidation catalyst but not an active decomposition catalyst. However, RuCl₃ is an active decomposition catalyst but not an active oxidation catalyst. PdCl₂ exhibits modest but detectable activity for all three formic acid reactions (decomposition, dehydration and oxidation). IrCl₃ is a relatively active catalyst for all three HCO₂H reactions. A comparison of the catalytic activities of the four noble metal chlorides for HCO₂H decomposition under conditions where both the dehydration and air oxidation reactions are suppressed (4.4% aqueous HCO₂H. Ar atmosphere) indicates the relative catalytic activity sequence: Ir Ru > Pd Rh (inactive).Portions of this work were presented at the 204th National Meeting of the American Chemical Society, Washington, DC, August 1992, paper INOR 124 in abstracts. For part 2 of this series see D. E. Linn Jr, R. B. King and A. D. King Jr, J. Molec. Catal., 80, 165 (1993). 0340-4285.     

Samarium Barbier reactions of alpha-iodomethyloxazoles and thiazoles with aliphatic aldehydes

[reaction: see text] The reductive coupling of substituted alpha-iodomethyloxazoles and thiazoles with aliphatic aldehydes under Barbier conditions provides an effective method for the direct incorporation of intact heterocyclic systems.     

3-Bromocyclohexane-1,2-dione as a useful reagent for Hantzsch synthesis of thiazoles and the synthesis of related heterocycles

We describe the use of 3-bromocyclohexane-1,2-dione, an air stable, versatile reagent for the Hantzsch thiazole synthesis and the synthesis of other closely related heterocycles.     

Palladium-catalyzed cyclization reactions : Unique synthesis of condensed thiazoles

The facile synthesis of 3-methylene-2,3-dihydro-5H-thiazolo-[3,2-c]pyrimidin-5-ones ($\text{9}$) has been performed by the catalytic action of a Pd(II) salt on 4-propargylthiopyrimidin-2(1H)-ones ($\text{6}$).Similar Pd(II)-catalyzed cyclization of 3-propargylthio-1,2,4-triazin-5(2H)-ones ($\text{10}$) gives 6-methylene-6,7-dihydro-4H-thiazolo[2,3-c](1,2,4]-triazin-4-ones ($\text{11}$) as a main product. 3-Methylene-2,3-dihydro-7H-thiazolo[3,2-b][1,2,4]triazin-7-ones ($\text{12}$), the regioisomers of $\text{11}$ are provided by a base-catalyzed cyclization of [ulbar 10].     

二氧化碳: 一种同时提供亲核中心保护和亲电中心活化的试剂 XI:2-取代四氢噻唑的新合成方法

四氢噻唑和正丁基锂反应生成的N-锂代四氢噻唑(2)与二氧化碳作用生成N-羟酸锂盐3; 3然后在叔丁基锂作用下失去2-位质子形成相应的2-位碳阴离子4; 该碳阴离子和一系列亲电试剂反应, 并在酸性条件下除去保护基团得产物-2-取代四氢噻唑7. 在此过程中, 二氧化碳既是氨基的保护基团, 同时又活化了2-位亲电中心.此方法不需分离各步中间体, 产率中等.     

Isomerization of 3-aryl-4-sulfolenes and their reaction with some nucleophilic reagents

Bases convert 3-(4-substituted phenyl)-4-sulfolenes to 3-aryl-3-sulfolenes, which are subsequently isomerized to 3-aryl-2-sulfolenes. The ratios of the products depend on the character of the substituent in the phenyl ring, and electron-acceptor substituents accelerate the isomerization.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1072–1077, August, 1975.     

Preparation and characterization of adducts of silicon tetrafluoride with thiazoles

Stable solid adducts of silicon tetrafluoride with the following thiazoles have been prepared: 2-aminothiazole, 2-amino-5-methylthiazole, 2-amino-6-methylbenzothiazole, 2-amino-7-nitrobenzothiazole and 2,4-dimethylthiazole. These adducts have been charactertsed by chemical and infrared spectral analysis. In all the cases except that of 2,4-dimethylthiazole (SiF₄·2L) the composition is 1:1. Both exocyclic and endocyclic nitrogen atoms are the coordinating centres in all the four cases while only endocyclic participates in coordination in the case of 2,4-dimethylthiazole. No indication has been found for the involvement of sulphur in coordination. Probable structures of these adducts have been proposed in which silicon is hexacoordinate.     

Preparation and some reactions of 3-oxazoline N-oxides

Substituted 3-oxazolines react with m-chloroperoxybenzoic acid to give the corresponding 3-oxazoline N-oxides. These heterocyclic nitrones underwent molecular rearrangements, but would not react with 1,3-cyclo-addition type reagents.