O-正丙基硫代磷酰二氯硫逐-硫赶重排反应的研究

硫代磷酰酯的硫逐-硫赶重排,即Pistschimuka反应,一直是吸引人们广泛兴趣的课题。O-正丙基硫代磷酰二氯酯(n-ProP(S)Cl_2,Ⅰ)经此重排得到的正丙硫基磷酰二氯酯(n-PrsP(O)Cl_2,Ⅱ)是一重要的化工原料,它是近十年来国外新开发的一类具有对抗性有着优异杀虫活性的丙硫基(硫赶)磷酰酯类新农药生产的关键中间体。由于Ⅰ与其甲、乙基同系物相比,碳链较长,该重排反应较难进行。我们引入了新型催化     

水杨酰腙与磷酰二氯的缩合反应

一些水杨酸的衍生物具有生物活性早有报道.本文研究水杨酰腙与硫代磷酰二氯或磷酰二氯缩合时可能发生的不同关环方式,并通过对反应产物的生物活性测定寻找有效的杀菌剂. 我们发现,在三乙胺存在下水杨酰腙1与硫代磷酰二氯2在四氢呋喃中反应主要以酮式关环生成3类化合物,而与磷酰二氯反应则主要以烯醇式关环生成4类化合物.     

O-乙基硫代磷酰二氯合成反应的动力学参数测定及条件选择

反应动力学;O-乙基硫代磷酰二氯合成反应的动力学参数测定及条件选择     

硫代磷酰二氯与邻苯二酚反应

苯基硫代膦酰二氯与邻苯二酚在三乙胺存在下生成螺环五配位磷化物3.烷氧基, 烷胺基,烷硫基,烷基,苄基硫代磷酰二氯与邻苯二酚反应得到六配位磷化物8.讨论了这些反应的机理.     

硫代四配位磷化物与邻苯二酚反应

前文报^[1]道的硫代磷酰二氯在三乙胺存在下与邻苯二酚反应,不仅具有理论意义,而且是合成该类磷化物的新方法。本文将继续报道硫代磷酰一氯以及其它硫代四配位磷化物与邻苯二酚反应的结果,以期进一步揭示这类反应的本质及其影响因素。     

S-烷基-O-多氯苯基硫代磷(膦)酸衍生物的合成及杀菌活性研究

O,O-二烷基硫代磷(膦)酸酯与三氯氧磷发生异构化氯化反应生成S-烷基硫代磷(膦)酰氯,后者在缚酸剂存在下与多氯酚反应得到标题化合物。此类化合物也可以用传统方法,从S-烷基硫代磷酰二氯先后与多氯酚及其它亲核试剂反应得到。对所合成的28个新化合物的平碟试验表明,在0.005%浓度下对小麦赤霉等12种植物病菌均表现了明显的抑制活性。     

S—烷基—O—多氯苯基硫代磷（膦）酸衍生物的合成及杀菌活性研究

Ｏ，Ｏ－二烷基硫代磷（膦）酸酯与三氯氧磷发生异构化氯化反应生成Ｓ－烷基硫代磷（膦）酰氯，后者在缚酸剂存在下与多氯酚反应得到标题化合物，此类化合物也可以用传统方法，从Ｓ－烷基硫代磷酰二氯先后与多氯酚及其它亲核试剂反应得到。对所合成的２８个新化合物的平碟试验表明，在０．００５％浓度下对小麦赤霉等１２种植物病菌均表现了明显的抑制活性。     

三氯化铝催化硫的同位素交换

研究了³⁵S与>C=S、→P=S、→C—S—S—C←、→C—SH等类型硫化物用三氯化铝催化的交换反应.二硫化碳、硫代磷酰氯、乙基硫代膦酰二氯、苯基硫代膦酰二氯等用此法交换,均得到良好的化学产率与放射产率.二硫化碳或硫代磷酰氯与三氯化铝、硫共热,显示三个顺磁共振峰,因此初步推测交换反应为自由基反应.含有R—O—P键的→P=S类化合物与三氯化铝发生副反应,故未能很好交换.二乙基化二硫的交换率颇低,乙硫醇则无交换.     

(+)-1R,3R(3S),5S-2,4,3-二氮磷杂二环[3.2.1]辛烷衍生物的不对称合成

用(+)-顺式-1R,3S-1,2,2-三甲基-1,3-环戊二胺1为手性诱导试剂分别和几类硫代磷酰二氯2a—k反应,合成了11个新型的含手性磷原子的(+)-1R,3RS,5S-2,4,3-二氮磷杂二环[3.2.1]辛烷的衍生物3a-k.3(1R,3Rs,5S)由两个不等量的非对映异构体3’(1R,3R,5S)和 3"(1R,3S,5S)组成,d.e.值对 3’为 6.2—83.6％,对3"为50.4—100％,表明3的合成是经过不对称反应实现的.苯氧基硫代磷酰二氯2e和1的反应具较高的光学选择性,产物中R磷原子异构体3’e的含量占90％;N,N-二烷基胺基硫代磷酰二氯2h,2i和1反应时,只得到含S磷原子的异构体3"h和3"i,为立体专一性反应.     

硫代磷酰基硫脲与某些含氯双官能团试剂的成环反应

Ｏ－乙基－Ｎ－异丙基硫代磷酰硫脲衍生物与氯乙酰氯、二氯乙酰氯及三氯乙酰氯，在碱存在下可发生关环反应，得到相应的噻唑啉酮类衍生物，讨论了不同试剂及反应条件对产物结构的影响，而Ｏ－乙基－Ｎ－异丙基硫代磷酰硫脲与氯乙醛关环，则生成相应的噻唑衍生物，所有化合物经元素分析、＾１ＨＮＭＲ、ＩＲ及ＭＳ证实，其中部分化合物显示出一定的除草活性。     

催化裂化过程中热裂化反应与二次反应的研究

利用连续式小型提升管催化裂化实验装置,研究了重油催化裂化过程中热裂化反应和二次反应的特点;考察了反应温度、剂油比和油气停留时间对热裂化和二次反应（氢转移和异构化反应）的影响;给出了不同反应条件下催化裂化过程中的过裂化点,考察了过裂化点前后热裂化反应在催化裂化过程中所占比例及氢转移和异构化反应的变化。结果表明,降低反应温度,缩短停留时间,增加剂油比可以抑制催化裂化过程中不利的热裂化反应,有利于氢转移和异构化反应的发生;在由反应温度、剂油比和停留时间引起的过裂化点前后,热裂化、氢转移和异构化反应表现出各自的变化特点。     

Kinetics and mechanisms of transalkylation and disproportionation of meta‐diethylbenzene by triflic acid catalyst

The kinetics of transalkylation and isomerization of meta‐diethylbenzene in the presence of benzene using triflic acid as a catalyst has been investigated. High catalytic activity of the triflic acid catalyst was observed in homogeneous liquid‐phase reactions. On the basis of the product distribution obtained, transalkylation, disproportionation, and isomerization reactions have been considered and the main product of the reaction was ethylbenzene. These reactions are conducted in a closed liquid batch reactor with continuous stirring under dry nitrogen and atmospheric pressure over the temperature range of 288–308 K. The main transalkylation, disproportionation, and isomerization reactions occurred simultaneously and were considered as elementary reactions. The apparent activation energy of the transalkylation reaction was found to be 35.5 kJ/mol, while that of disproportionation reaction was 42.3 kJ/mol. The reproducibility of the experimental product distribution occurred with an average relative error of ±2%. © 2003 Wiley Periodicals, Inc. Int J Chem Kinet 35: 555–563, 2003     

Au/HZSM-5沸石催化剂的正丁烷异构化反应性能的研究

采用脉冲微反装置评价了纯正丁烷、含有不同比例异丁烷的混合丁烷在Au改性的纳米HZSM-5催化剂上的反应活性和异构化选择性。结果表明,在300℃时,载金量为1.31%的催化剂上纯正丁烷原料的转化率可达7.0%,异丁烷选择性可达80%以上。相比之下,在纳米HZSM-5载体上正丁烷的转化率只有0.55%,异丁烷选择性仅为11.67%。在Au负载量为0.12%~1.91%,随着Au负载量的增加,正丁烷转化率先增后减,异丁烷选择性在低负载量时增加明显。在反应温度低于400℃时,纯正丁烷在载金催化剂上主要发生异构化反应;高于400℃时,主要发生裂解和芳构化等反应,即400℃是正丁烷在脉冲微反条件下异构化和裂解等反应的分水岭。另外,混合丁烷的组成对正丁烷异构化反应有一定影响,但在适当温度下正丁烷异构化时裂解产物很少,表现出金属-酸双功能催化特征。Au⁺在反应中发挥了脱氢和加氢作用。     

Non-metathesis reactions of ruthenium carbene catalysts and their application to the synthesis of nitrogen-containing heterocycles

Non-metathesis reactions of ruthenium carbene catalysts, such as olefin isomerization, hydrogenation, radical reaction, activation of silane, cyclopropanation, epimerization cocyclopropane, [3 + 2] cycloaddition, and cycloisomerization, are summarized. The utility of these reactions was demonstrated by the synthesis of indole using olefin isomerization and subsequent ring-closing metathesis, the synthesis of indoline using cycloisomerization, and the synthesis of the putative structure of fistulosin using cycloisomerization as a key step.     

Effect of H_2S on the transformation of 1-hexene over NiMoS/γ-Al_2O_3 with hydrogen

The effect of H2S contents on the transformation of 1-hexene with hydrogen over NiMoS/γ-Al2O3 catalyst was investigated.Inhibition of H2S on both hydrogenation and isomerization reactions of olefin has been demonstrated.And the promotion effect of H2S on the formation of C6 thiols and C12 thioethers has also been observed.It was found out that there was only one type of active site on the NiMoS/γ-Al2O3 for reactions which include hydrogenation reaction,isomerization reaction and sulfides formation reaction,...     

Photochemical reaction kinetics in optically dense media: The influence of thermal reactions

The kinetics of photochemical reactions in optically dense media essentially free from diffusion was considered. The photochromic isomerization A ↔ B was studied as an example. If thermal isomerization is possible, a stationary state is achieved in time determined by rate constants for the thermal reactions. The concentration wave profile is changed during the photochemical reaction propagation. Low values of thermal reaction constants and decrease in sample optical density during photochemical isomerization were found to be essential for maximal wave penetration into the sample. Sharp concentration gradients of A and B can be observed when both the optical density is increased during photochemical isomerization and the quantum yield of the direct photochemical reaction A → B is higher than that of the reverse photochemical reaction B → A.     

An examination of density functional theories on isomerization energy calculations of organic molecules

Long-range corrected (LC) density functional theories (DFTs) were applied to the isomerization energy calculations of organic molecules to make clear why conventional DFTs including B3LYP have given poor isomerization reaction energies. Combining with local response dispersion (LRD) method, we performed LC-DFT calculations for the benchmark set of isomerization reactions. Consequently, we found that LC-DFT?+?LRD methods give accurate reaction energies equivalent to up-to-date DFTs containing many semi-empirical parameters. This result indicates that long-range exchange and intramolecular dispersion correlation interactions, which have been neglected in conventional DFTs, play prominent roles in isomerization reactions. However, we also found that these interactions are not sufficient to give accurate isomerization energies especially for cyclization reactions. Considering that Gaussian-attenuated LC-DFTs (LCgau-DFTs) give better isomerization reaction energies than LC-DFTs, we suggested that the isomerization energies will be further improved by correcting the short-range part of exchange functionals in DFT with keeping the whole long-range exchange interactions.     

Isomerization of cyclic hydrocarbons mediated by an AlCl3-based ionic liquid as catalyst

Cyclohexane and methylcyclopentane isomerization were carried out under mild conditions using an ionic liquid consisting of n-butylpyridinium chloride and aluminum chloride as catalyst. The ionic liquid showed reasonably high catalytic activity in both reactions with a selectivity to corresponding products of 100%. In the case of cyclohexane isomerization, the thermodynamic equilibrium methylcyclopentane ⇌cyclohexane was almost achieved. For the reaction of cyclohexane isomerization, the kinetic study was performed, and the rate constants and the activation energy of the process were determined. This revised version was published online in June 2006 with corrections to the Cover Date.     

改性Y沸石上的氢转移反应

本文试图用环已烯和邻二甲苯两典型反应考察改性Y沸石的氢转移反应性能。发现在改性Y沸石上环已烯的氢转移, 异构化和聚合反应时发生。在反应开始时SY沸石的氢转移反应和异构化反应活性与铝含量之间的关系与沸石强酸量和铝含量的关系一致, 呈火山形曲线, 极大值在Al/(Al+Si)为0.15左右, 结焦以后反应总转化迅速下降, 且氢转移活性和异构化活性随铝含量减少而单调下降。USY沸石的氢转移活性大幅度降低。在改性Y沸石上邻二甲苯异构化和歧化反应同时进行, SY沸石的歧化反应变化规律与环乙烯氢转移反应相似。当沸石样品中有大量非质子酸位存在时, 两个反应的数据会出现予盾。