高纯度(>98%)三芳基-2-硼酸的合成

以卤代芳烃为原料,经硼酸化反应和Suzuki偶联反应合成了一系列三芳基-2-硼酸化合物,收率67.4%~70.1%,纯度均98%,其结构经1H NMR和元素分析确证。     

2,5-二芳基噻吩类化合物的高效绿色合成

无需金属和碱的催化,以1,4-二芳基取代-1,3-丁二炔与Na2S·9H2O为反应底物,80℃下DMF中合成了2,5-二芳基噻吩类化合物,考察了反应物苯环上电子效应和空间位阻对硫杂环化反应的影响.结果表明:反应物苯环上的吸电子或电子取代基团均对反应产物的分离产率影响不大;空间位阻较大的反应底物硫杂环化反应的收率略有降低,各种目标化合物产率为88%~100%.     

2,6-二甲氧基-3-烷基-1,4-苯醌的合成

取代的1,4-苯醌类化合物广泛存在于自然界的植物和动物体内。其中有一部分已证明具有明显生理活性。最重要的取代1,4苯-醌类化合物是泛醌(ubiquinone)和质体醌(plastoquinone)。它们是动物线粒体呼吸链和植物光合作用链中重要的非蛋白电子载体。2,6-二甲氧基-1,4-苯醌(4)存在于许多植物的树皮和木心中。它的生理作用目前还知道得     

新颖的纳米镍催化芳基硼酸与芳基溴的偶联反应

纳米镍用于催化芳基硼酸与芳基溴的偶联反应，合成了一系列4，4′-双烷基环己基联苯类液晶，纳米镍在相转移剂十六烷基三甲基溴化铵的存在下回流反应15h，目的产物的收率为60%-65%。讨论了纳米镍催化偶联反应的可能活性位，镍催化剂经SEM-EDS表征平衡粒径为80nm，定量分析表明氧含量为33%；XRD测试结果表明纳米镍体相以单质态存在，但其特征谱线的d值普遍增大；由XPS分析得聘书纳米镍的结合能（2p3/2和2p1/2)为854.1eV和871.8eV，峰间距为17.7eV，表明纳米镍是以介于单质镍和氧化镍之间的价态存在。     

Suzuki偶联反应合成三联苯中的副产物研究

以4-(4′-乙基)联苯硼酸和4-丙基溴苯为原料,采用Suzuki偶联反应在Pd(PPh3)4催化下合成了4-乙基-4″-丙基-1,1′∶4′,1″-三联苯液晶,其结构经MS表征。考察了催化剂、反应时间、保护气体、碱等对反应的影响,找出了产生自偶联、脱硼酸和芳基-芳基互换3种副产物的影响因素,并对其产生的机理进行了讨论。     

芳基亚磺酸钠自身偶联合成二芳基砜

在二价铜促进下,芳基亚磺酸钠通过分子间脱硫,发生自身偶联,高选择性高产率地合成了对称性的二芳基砜类化合物。反应无需惰性气体保护,条件温和,具有良好的官能团耐受性,可以用于二芳基砜衍生物的高效合成。     

2,5-二(2-羟乙氨基)-1,4-苯醌合成方法的改进

以对苯二酚和乙醇胺为原料,直接合成2,5-二(2-羟乙氨基)-1,4-苯醌,并对产物进行红外、紫外、质谱及核磁表征.采用正交设计法对实验条件进行优化,乙醇为溶剂,对苯二酚和乙醇胺物质的量比为1∶5,在50℃下,反应2h,最高产率达到72.8%.产物为针状晶体,纯度较高.     

反式-2,5-二芳基四氢呋喃合成的新方法

以(±)4,10-二氧杂三环[5,2,1,0_2,6]-癸-8-烯-3-醇为原料,经过芳基化、氧化、芳基化、环化、热分解和加氢反应,得到PAF新的拮抗物反式-2,5-二芳基四氢呋喃,并合成了化合物8.     

1,3-二芳基-1丙酮类化合物的合成

以取代苯乙酮和取代芳香醛为原料,制得一系列1,3-二芳基-1-氧代丙烯类化合物(1a~1j); 1a~1j和对甲苯磺酰肼(2)经还原反应合成了10个1,3-二苯基-1-丙酮类化合物(3a~3j, 3h为新化合物),其结构经¹H NMR, ¹³C NMR, IR和HR-MS（ESI）确证。研究了碱、溶剂、温度和投料比γ[n(1a)/n(2)/n(碱)]对3a产率的影响。结果表明：γ=1/2/2,磷酸钾为碱,乙醇为溶剂,于80 ℃反应4 h, 3a产率最高（80%）。     

α-二亚胺钯配合物的合成及催化Suzuki偶联反应

设计合成并表征了3个具有不同骨架结构的α-二亚胺钯配合物,并在有氧条件下催化不同溴代芳烃与芳硼酸的Suzuki偶联反应,重点考察了配合物骨架结构、碱性强度、溶剂极性和不同反应温度对催化反应的影响。结果表明,α-二亚胺类钯配合物能催化Suzuki偶联反应,采用质子溶剂、无机碱,以及较高反应温度都有利于偶联反应的进行,能够高效制备一系列联芳类化合物。     

Hydrogen bonding and molecular vibrations of 2,5-dihydroxy-1,4-benzoquinone

Intramolecular hydrogen bonding in 2,5-dihydroxy-1,4-benzoquinone has been investigated by means of quantumchemical calculations and vibrational spectroscopy. Both computations at the MP2/6-31+G** level as well as FT-IR and FT-Raman spectra are in agreement with the predominance of the C_2h conformer with two intramolecular hydrogen bonding interactions. The spectra were interpreted with the aid of normal coordinate analysis based on a scaled Becke3–Lee–Yang–Parr/6-31G* density functional force field. The general scale factors introduced recently by Rauhut and Pulay for this theoretical level allowed a reliable assignment of most of the fundamentals. The scale factors for vibrations affected strongly by the intramolecular hydrogen bonding interaction needed some adjustment and hence were re-optimized in the present study. The final scaled force field reproduced the experimental frequencies of the molecule by a weighted mean deviation of 8.8 cm⁻¹. Based on the calculated results, 32 from a total of 36 fundamentals were assigned in the vibrational spectra of 2,5-dihydroxy-1,4-benzoquinone revising and extending the assignments of earlier less sophisticated investigations.     

2,5,-Dimethoxy- and 2,5-di-n-butoxy-1,4-benzoquinone reactions and polymerization with 1,6-hexanediamine

The serendipitous formation of 2,5-dimethoxy- 1,4-benzoquinone is reported from the reaction of 1,4-benzoquinone with methanol, DABCO, and paraformaldehyde. This monomer, and its di-n-butoxy analog, are also available from 2,5-dihydroxy-1,4-benzoquinone. These materials are capable of novel polycondensation reactions with diamines such as 1,6-hex-anediamine. Use of m-crexsol as polymerization solvent gave a dark, insoluble product while various amide solvents lead to orange or pink polymers that had average degrees of polymerization from 5 up to >30. These polymers, Plus model compounds obtained from 1-aminopropane and N,N'- dimethyl-1,6-hexanediamine, were characterized by FTIR, solution, and solid-state NMR.     

Reaction of N-substituted 2,5-dialkyl-1,4-benzoquinone imines with arenesulfinic acids

Reactions of N-aroyl-, N-arylsulfonyl-, and N-(N-arylsulfonylbenzimidoyl)-2,5-dialkyl-1,4-benzoquinone imines with sodium arenesulfinates in acetic acid gave the corresponding 1,4-, 6,1-, and 1,6-addition products. Variation of the size and donor power of substituents in positions 2 and 5 of the quinoid ring almost does not affect the ratio of the addition products, which is determined mainly by the nature of substituent on the nitrogen atom.     

Determination of zirconium,thorium and scandium with 2,5-dihydroxy-1,4-benzoquinone

Zirconium is quantitatively precipitated by 2,5-dihydroxy-1,4-benzoquinone and is separated from scandium in 1 N hydrochloric acid solution. Thorium is separated at pH 0.5 from uranium(VI), cerium(IV), lanthanum, yttrium and scandium. Scandium is quantitatively precipitated by this reagent in the pH range 1.4–2.0 and at pH 1.5 equivalent amounts of lanthanum do not interfere; small amounts of yttrium cause interference.     

Substituted 2,5-Diaryl-2H-Tetrazoles

Elimination of nitrogen from diaryl substituted 2H-tetrazoles during the first step of thermal decomposition yields diphenylnitrileimines. In spite of the. drastic reaction conditions of the melt, they react relatively selective, giving two main products, the 1,2,4,5-tetrazines and 1,2,4-triazoles (together more than 70%). The triazoles are formed if the separation of nitrenes from the nitrileimine is favoured. Therefore, the mass losses found for the first step exceed the values calculated for N₂ only. The product mixture after the first TG step was investigated by the title methods, and especially by means of computer-aided MS analysis.     

Visible Light-Induced Synthesis of 3,4-Diarylthiophenes from 3,4-Diaryl-2,5-dihydrothiophenes

Using a catalytic amount of platinum(II) terpyridyl complex 3, 3,4-diarylthiophenes (2a-f) could be synthesized from 3,4-diaryl-2,5-dihydrothiophenes (1a-f) under visible light (λ > 450 nm) irradiation in degassed CH(3)CN. Spectroscopic study and product analysis reveal that the reaction is initiated by photoinduced electron transfer from 3,4-diaryl-2,5-dihydrothiophenes to platinum(II) complex 3, leading to the formation of 3,4-diarylthiophenes.     

Tunnelling effects in the double proton transfer reaction of 2,5-dihydroxy-1,4-benzoquinone

Two dynamic models were used to investigate the double proton transfer reaction of 2,5-dihydroxy-1, 4-benzoquinone. The stationary points of the potential energy surface were located using the AM1 method. A model two-dimensional potential surface based on the Cartesian coordinates of the protons is constructed. According to the first model, the synchronous and asynchronous mechanisms of the reaction are treated separately. In the second model the two-dimensional vibrational problem is solved on the corresponding potential energy surface. The unimolecular rate constants are calculated in terms of the RRKM theory and the one- and two-dimensional approximations are compared. The second model predicts the dominant role of tunnelling and the synchronous and asynchronous processes can hardly be separated.     

Synthesis of 1,4-diaryl-2,5-dioxopiperazines

A new method for the synthesis of 1,4-dlaryl-2,5-dioxopiperazines by the condensation of chloroacetanilides in the presence of sodium in anhydrous solvents, has been developed. The evolution of hydrogen shows the nucleophilic nature of the condensation.