苯甲醛肟与炔丙醇偶极环加成反应的理论研究

用密度泛函理论(DFT)方法在B3LYP/6-31G*水平上研究了苯甲醛肟与炔丙醇加成反应的微观机制和热力学、动力学行为. 结果表明, 在苯甲醛肟与炔丙醇加成反应过程中, 8个可能反应通道的过渡态中均形成非平面五元环结构, 其中苯甲醛肟的Z、E构型特征得到了部分保留, 但主要部分的键长、键角均发生了变化, 电荷也进行了重新分布. 苯甲醛肟以羟基型参与反应的4个反应通道均为吸热反应和热力学非自发过程, 它们均具有较高的反应势垒、较慢的反应速率和较小的平衡常数; 而以离子型参与反应的四个反应通道均为放热反应和热力学自发过程, 它们的反应势垒较低, 反应速度较快, 平衡常数也较大, 故苯甲醛肟应主要以离子型参与反应. 炔丙醇的两种取向对应着加成反应的两种产物, 反应达到平衡后, 3-羟甲基二氢异噁唑为主要产物.     

Ni催化的碳(sp2)-碳和碳(sp2)-杂交叉偶联反应

综述了Ni催化的碳(sp²)-碳和碳(sp²)-杂交叉偶联反应. 主要反应类型有: Heck反应、Sonogashira反应、Kumada-Corriu反应、Negishi反应、Stille反应、Suzuki反应、Ullmann反应、C—N偶联反应、C—O偶联反应、C—P偶联反应和C—S偶联反应. 详细地介绍了各个反应的底物要求、反应条件、反应选择性和产率. 最后, 我们对Ni催化的反应机理研究也作了总结.     

Kinetics of phenol oxidation with ozone in a thin layer on a solid surface

Ozone has been reacted with phenol in thin supported layers, and the dynamics of this reaction has been investigated. The stoichiometry of this reaction coincides with the stoichiometry of the same reaction in solution. Specific reaction rate (β) has been determined for various phenol conversions. The effective rate constant of the reaction, estimated by extrapolating β to zero reaction time, is significantly higher than the rate constant of the reaction in solution. The reaction between ozone and phenol is diffusion-controlled. The reaction products form a barrier layer, which protects the deeper phenol layers against ozone. The barrier layer is as thick as 8–15 phenol monolayers.     

低热固相反应的反应机理研究(Ⅰ)——冷融熔机理和冷溶熔机理的模型

本文提出了低热固相反应的冷融熔机理和冷溶熔机理,其中冷融熔机理主要针对于不含结晶水的反应体系,冷溶熔机理主要针对于含结晶水的反应体系,并对低热固相反应动力学提出冷融熔/冷溶熔、扩散、反应、成核、生长的五步机理。两种机理都避开了分子在固相晶格中的扩散,从而对低热固相反应的扩散问题进行了有效的解释,并给出了低热固相反应的热力学和动力学判据。     

Mechanistic Study on the Ozone‐Mercury Reaction and the Effect of Water and Water Dimer Molecules

The thermodynamics and mechanism of the reaction of elemental mercury with ozone has been studied computationally. The effect of water and water dimer molecules on the reaction has also been investigated. For dry reaction, we obtained two pathways and geometry optimization, atoms in molecules analysis and vibrational frequencies of all component of reaction have been used for confirming of reaction mechanism. Thermodynamic variable of reaction has been calculated. For the reaction in the presence of the water, our studies focus on ozone‐mercury complex reaction with water and water dimer and obtained the mechanism of reactions. Comparison of wet and dry reaction shows the energy profile of reaction decreases with water molecule correspond to experimental prediction. Calculated thermodynamic variable of all reaction shows the Gibbs free energy of reaction decreases with the number of water molecule.     

离子液体介质中有机合成及不对称催化反应研究新进展

总结了近年离子液体中有机合成反应及不对称催化反应研究新进展，包括还原 反应、氧化反应、Friedel-Crafts反应、Diels-Alder反应、交叉偶联反应、加成 反应、环缩合反应、自由基反应、Witting反应、重排反应、不对称催化反应及其 它合成反应。     

The photo-dehydro-Diels-Alder (PDDA) reaction

The photo-dehydro-Diels-Alder (PDDA) reaction is a valuable extension of the classical Diels-Alder (DA) reaction. The PDDA reaction differs from the DA reaction by the replacement of one of the C-C-double bonds of the diene moiety by a C-C triple bond and by the photochemical triggering of the reaction. This entails that, in contrast to the DA reaction, the PDDA reaction proceeds according to a multistage mechanism with biradicals and cycloallenes as intermediates. The PDDA reaction provides access to a considerable variety of compound classes. For example, 1-phenylnaphthlenes, 1,1'-binaphthyls, N-heterocyclic biaryls, and naphthalenophanes could be obtained by this reaction.     

金属参与的正电子放射性药物的合成进展

随着正电子发射断层显像技术的高速发展,正电子放射性药物的合成近年来已成为药物合成领域的热点之一.本文综述了金属参与的放射性同位素标记药物及中间体的合成方法,反应类型包括Stille偶联反应、Suzuki偶联反应、Heck偶联反应、Sonogashira偶联反应、羰基化反应、金属-卤素置换反应和点击反应等.     

手性磺酰胺有机小分子催化剂在不对称催化反应中的应用进展

有机小分子催化的不对称合成反应是目前研究最为活跃的领域之一.综述了磺酰胺类衍生物作为小分子催化剂在不对称反应(Michael加成反应、Mannich反应、羟醛缩合反应等)中的应用,讨论了磺酰胺中NH的酸性以及氢键性质在不对称催化反应中的的作用.     

Highly efficient synthesis of linear pyrrole oligomers by twofold Heck reactions

The twofold Heck reaction of the vinylpyrroles 3a and 3b with the iodobenzenes 4a-c led to the linear pyrrole oligomers 5, 6, and 7. The synthesis of both symmetrical and unsymmetrical oligomers, such as 10a and 10b, was also accomplished by a Heck reaction of 8 and 9 and by a Heck reaction of 3a and 11 followed by a Wittig reaction and a second Heck reaction with 8. The pentacyclic oligomers 14 and 19 were prepared by a twofold Heck reaction of 13 with 4 and by a twofold Heck reaction of 15 with 16 followed by a Wittig reaction and a twofold Heck reaction with 8.     

磷钨酸铝催化合成对甲氧基苯乙酮

以H3PW12O40和AlCl3·6H2O为原料合成AlPW12O40,以此为催化剂研究苯甲醚与乙酸酐的酰基化反应,其主要产物为对甲氧基苯乙酮.采用正交试验确定酰化反应的适宜条件为:苯甲醚0.1 mol,苯甲醚与乙酸酐物质的量比为1∶1.5,催化剂用量1 g,反应时间4h,反应温度100℃,在此条件下,产品收率达到69.80％.考察了不同反应底物及不同酰化试剂对反应的影响和不同磷钨酸盐的催化效果,比较了不同加热方式对催化反应的影响.结果表明,磷钨酸铝的催化活性最好,微波加热合成目标产物效果更好.     

负载型Heck反应催化剂的研究进展

Heck反应是一类重要的C-C偶联反应,传统的均相Heck反应催化剂存在分离和回收困难等问题;近年来负载型Heck反应催化剂的研究引起了人们的广泛关注.本文综述了钯基和非钯基负载型Heck反应催化剂的研究进展,评述了不同载体上催化活性组分对Heck反应的特点,并展望了其发展趋势.     

Study of the reaction between boron trifluoride methanol complex and sodium methoxide

The reaction between boron trifluoride methanol complex and sodium methoxide in methanol solution was investigated using conductivity as the reaction indicator. The reaction conditions were examined and a mechanism of this reaction was proposed. Moreover, proper reaction conditions were proposed for boric acid preparation using this reaction.     

离子液体共价键功能化氧化石墨烯负载催化材料催化反应研究进展

氧化石墨烯由于其独特的结构和性能赋予了它作为催化剂的先天优势,功能化的氧化石墨烯为其应用领域的拓展和效果提升提供了更多的发展契机,成为目前的研究趋势,离子液体功能化的氧化石墨烯结合二者自身优势的基础上,并由于协同作用具有更加优异的催化性能,广泛应用于众多反应中.我们针对离子液体共价键功能化的氧化石墨烯负载催化剂常见的催化反应,包括环加成反应,氧化反应,偶联反应,酯交换反应,乌尔曼反应,重排反应,光催化和电催化在近年来的研究进展进行了相关综述.     

HCN + OH→CN + H2O反应理论研究

The reaction path of the reaction HCN + OH→ CN + H2O was traced with Fukui's theory of intrinsic reaction coordinate by using ab initio MO method (at UMP4/6-31G** level) with gradient technique. On this basis, the dynamics properties along the reaction path was investigated by reaction path Hamiltonian theory. The rate constants of this reaction at different temperatures were calculated by conventional and variational transition state theory with tunneling correction. The theoretically calculated rate constants are in good agreement with experimental results, this shows that the title reaction is an one step, direct reaction.     

脯氨酸催化的不对称有机反应

脯氨酸作为一种结构简单、商品化的、廉价小分子手性催化剂,在多种不对称催化反应中表现出非常好的催化性能,本文综述了近年来脯氨酸直接催化的不对称有机反应涉及Aldol反应,Mannich反应,Michael反应,Diels-Alder反应,直接α-胺化反应,α-氧胺化反应,Baylis-Hillman反应,还原反应和氧化反应的进展并展望了其应用前景。     

A catalyst-free novel synthesis of diethyl carbonate from ethyl carbamate in supercritical ethanol

Diethyl carbonate has been synthesized via the alcoholysis of ethyl carbamate in supercritical ethanol under catalyst-free conditions.The influences of various parameters such as reaction temperature,reaction time,reaction pressure,ethanol/ethyl molar ratios and reaction loading volume on the yield of DEC were studied systematically.The experimental results indicated that the alcoholysis of ethyl carbamate was greatly improved in supercritical ethanol.The optimal reaction conditions were as follows：a reaction temperature of 573 K,a reaction time of 30 min,a reaction pressure of 13.2 MPa,an ethanol/ethyl carbamate molar ratio of 10 and a reactor loading volume of 285 μL respectively.The optimal yield of DEC was 22.9%.     

荧光增白剂4,4′-二(4-磺酸钠苯乙烯基)二苯甲酮的合成

用Heck反应合成了4,4′-二(4-磺酸钠苯乙烯基)二苯甲酮.对Heck反应条件进行了改进,使用壳聚糖负载钯为催化剂并考察了催化剂的回收再利用情况.通过研究影响该反应的各种因素,如反应时间、反应温度、原料配比等,优化了实验条件,得到了较好的结果.     

N(4S)+CH3X(X=Cl、Br)反应机理的理论研究

The reaction of N(4S)+CH3X(X=Cl、Br) was studied by the ab initio method. The geometries of the reactants, transition states and products were optimized at the MP2/6-311+G(d,p) level. The corresponding vibration frequencies were calculated at the same level. The single-point calculations for all the stationary points were carried out at the MP2/6-311++G(3df,2p) and the QCISD(T)/6-311+G(d,p) levels using the MP2/6-311+G(d,p) optimized geometries. The energies of all the stationary points were calculated by the G2MP2 method. The results of this theoretical study indicate that the reaction has three reaction channels: H abstraction reaction channel a, Cl or Br abstraction reaction channel b and substitution reaction channel c. For the N(4S)+CH3Cl reaction, reaction channel a is the main reaction channel. Reaction channels b and c may have a slight contribution in the reaction. For the N(4S)+CH3Br reaction, reaction channel a is the main reaction channel. Reaction channels b and c may have some contribution in the reaction.     

Copper-catalyzed enantioselective Henry reactions of alpha-keto esters: an easy entry to optically active beta-nitro-alpha-hydroxy esters and beta-amino-alpha-hydroxy esters

The catalytic enantioselective Henry reaction of alpha-keto esters with nitromethane has been developed. The reaction conditions have been optimized by the screening of different chiral Lewis acids, solvents, and bases, and it was found that the copper(II)-tert-butyl bisoxazoline complex in combination with triethylamine catalyzed a highly enantioselective reaction giving optically active beta-nitro-alpha-hydroxy esters in high yields and with excellent enantiomeric excesses. The scope of the reaction is demonstrated by the reaction of a variety of different alpha-keto esters. The catalytic enantioselective Henry reaction of beta,gamma-unsaturated-alpha-keto esters proceeds as a 1,2-addition reaction exclusively, in contrast to the uncatalyzed reaction where both the 1,2- and 1,4-addition products are formed. It is demonstrated that the beta-nitro-alpha-hydroxy esters can be converted into, e.g., Boc-protected beta-amino-alpha-hydroxy esters in high yields and without loss of optical purity. The mechanism for the reaction is discussed, and it is postulated that both the alpha-keto ester and nitromethane/nitronate is coordinated to the metal center during the reaction course.