α,β-不饱和酮衍生物的合成

以2,3-二取代-4-(1-氧代-丙基)苯氧基乙酸、多聚甲醛、二甲胺盐酸盐为起始原料,在冰乙酸的催化下经曼尼西反应得到2,3-二取代-4-(2-二甲胺基亚甲基-1-氧代-丙基)苯氧基乙酸盐酸盐,然后经水解反应得到了目标化合物.该方法操作简便,收率较高,有较强的实验室应用价值.     

6-取代-l,4-环辛二烯的单重态氧反应——合成顺式-5,8-和反式-5,6-二取代-1,3-环辛二烯含氧衍生物的方便途径

以竹红菌甲素作敏化剂匹配高压钠灯产生单重态氧,在甲醇溶液中,氧化6-取代-1,4-环辛二烯(1),(2),并经亚硫酸钠还原,得到顺-5,8-二取代-1,3-环辛二烯和反-5,6-二取代-1,3-环辛二烯发。化合物(3)是在三氯乙烷溶液中,未经还原得到过氧化氢基取代-1,3-环辛二烯。基态分子的稳定构象决定了反应产物的立体选择性。这类反应为用光氧化方法合成顺-5,8-二取代和反-5,6-二取代-1,3-环辛二烯含氧衍生物提供了方便的途径。     

3-吡咯氧化吲哚参与不对称构建手性季碳中心的研究进展

氮杂季碳手性中心结构存在于许多生物活性分子或药物分子中,C3位含有氮原子的3,3'-二-取代氧化吲哚结构更是许多具有生物活性的天然产物或药物分子的核心骨架,以3-吡咯氧化吲哚作为亲核试剂不对称合成结构多样的3,3'-二取代氧化吲哚类化合物是一种可行的构建含氮杂季碳手性中心化合物的方法.综述了3-吡咯氧化吲哚通过分子内反应和分子间反应两种形式参与构建3,3'-二取代氧化吲哚类化合物的研究进展,并对构建含氮杂季碳手性中心化合物进行了展望.     

3-吡咯氧化吲哚参与不对称构建手性季碳中心的研究进展

氮杂季碳手性中心结构存在于许多生物活性分子或药物分子中,C3位含有氮原子的3,3'-二-取代氧化吲哚结构更是许多具有生物活性的天然产物或药物分子的核心骨架,以3-吡咯氧化吲哚作为亲核试剂不对称合成结构多样的3,3'-二取代氧化吲哚类化合物是一种可行的构建含氮杂季碳手性中心化合物的方法.综述了3-吡咯氧化吲哚通过分子内反应和分子间反应两种形式参与构建3,3'-二取代氧化吲哚类化合物的研究进展,并对构建含氮杂季碳手性中心化合物进行了展望.     

2,5-二取代-1,3,4-噻二唑类化合物的合成及应用研究

1,3,4-噻二唑类化合物是含有N、S原子的五元杂环化合物,具有重要的化学和生物应用价值。本文主要论述2,5-二取代-1,3,4-噻二唑类化合物的合成及其在抗腐蚀、抗磨擦、液晶、农药、医药、分析化学等方面的应用。     

1,2-二苯基-1,1,2,2-四乙氧基羰基乙烷的合成及密度泛函计算研究

在2,3-二取代丁二酸酯类化合物的合成研究中,化合物1,2-二苯基-1,1,2,2-四乙氧基羰基乙烷作为研究合成路线中的模型中间体,具有重要意义.设计并合成了该化合物,用电喷雾质谱、核磁和红外进行表征确认,并用Materials Studio程序中的密度泛函方法计算了该化合物的结构参数和振动频率,得到与红外图谱相一致的结果,确认了化合物的合成成功,为该化合物的进一步研究奠定了基础.     

1,5-二羧乙基-2,4-二氧六氢-1,3,5-三嗪的糖类衍生物的合成及生物活性

在氢氧化钠和四丁基溴化铵存在下,1,5-二羧乙基-2,4-二氧六氢-1,3,5-三嗪分别与乙酰溴代葡萄糖、乙酰溴代半乳糖、乙酰溴代乳糖作用,合成了1,5-二羧乙基-2,4-二氧六氢-1,3,5-三嗪的对应的糖酯,产率分别为42%、34%、30%,由元素分析、IR和1H NMR确认了所合成糖酯的结构.生测结果表明所合成的化合物具有较好的抗烟草花叶病毒(TMV)的活性.     

3种2-甲基-2-烷基-1,3-二硫杂环戊烷类化合物的合成

以对甲苯磺酸为催化剂, 3种酮类化合物和二硫代乙二醇在苯中共沸脱水,合成了 2 -甲基- 2 -乙基- 1, 3 -二硫杂环戊烷、2- 甲基- 2- 异丁基- 1, 3- 二硫杂环戊烷和 -2 -甲基- 2 -异戊基 1, 3 二硫杂环戊烷,产率分别为 71. 5%、74. 3%和 75. 6%,质量分数分别为 98 .8%、99. 1%和 98. 9%。经红外光谱分析、元素分析、核磁共振分析和色 -质联机分析确定了 3种产物的结构。     

串联式一锅法合成2,6-二氧杂双环[3.3.1]壬烷衍生物

利用6-庚烯-2,4-二醉与不同的醛酮化合物在三氯化锢和浓盐酸存在下,以二氯甲烷做溶剂进行Prins反应,得到一系列3,7-二取代-2,6-二氧杂双环[3.3.1]壬烷衍生物.该反应条件简单,三氯化锢在其中起关键作用.产物的相对构型用NOESY测试进行了表征.     

新的5-对羟基苄亚甲基-2-硫代-2,4-咪唑啉二酮苯磺酸酯的合成

以4-羟基苯甲醛和2-硫代乙内酰脲为原料高收率的合成了5-对羟基苄亚甲基-2-硫代-2,4-咪唑啉二酮,再将它与取代苯磺酰氯反应合成了标题化合物,它们的结构经1~HNMR、~(13)CNMR和元素分析确证.     

Preparation,hydrogen bonding and properties of polyurethane elastomers with 1,2,3-triazole units by click chemistry

Two kinds of diols containing 1,2,3-triazole units were synthesized through the azide-alkyne cycloaddition reaction between propargyl alcohol and 1,4-diazidobutane. One of the diols, (butane-1,4/1,5-diylbis[1H-1,2,3-triazole-1,4/1,5-diyl])dimethanol (BDTDO-1), containing 1,4/1,5-disubstituted 1,2,3-triazole regioisomers, was directly prepared under thermal condition without Cu(I) catalyst. The other diol, (butane-1,4-diylbis[1H-1,2,3-triazole-1,4-diyl])dimethanol (BDTDO-2), containing 1,4-disubstituted 1,2,3-triazoles, was prepared by Cu(I) catalyzed click chemistry. Then, two kinds of 1,2,3-triazole modified polyurethane elastomers (PUEs) were prepared from the reaction of 4,4′-methylenebis(phenyl isocyanate) and poly(tetramethylene ether) glycol, with BDTDO-1 or BDTDO-2 as the chain extender (CE). It was found that the introduction of 1,2,3-triazoles and their substitution positions had significant influences on the hydrogen bonding, thermal and mechanical properties of PUEs. Compared with the PUE prepared from 1,4-butanediol as the CE, the PUE containing symmetric 1,4-disubstituted 1,2,3-triazoles units in the main chains shows higher values of hydrogen bonding, physical crosslinking density, Young's modulus, tensile strength and melting temperature, while lower glass transition temperature, resulting from the rigid structure and the ability to form more hydrogen bonds. However, the introduction of asymmetric 1,4/1,5-disubstituted 1,2,3-triazole moieties decreases the values of hydrogen bonding, thermal and mechanical properties of PUE appreciably due to the destruction of the ordered structure of the hard segments.     

Roles of cyclic units in copolyethylene crystallization: a molecular dynamics simulation

Molecular dynamics (MD) simulations of several polyethylene copolymer chains containing 1,2-, 1,3- or 1,4-disubstituted cyclopentane or hexamethylene structures in the main chain (with 500 CH₂) are performed to investigate the influence of cyclic units on the crystallization properties of polyethylene (PE). From the isothermal relaxation process it is found that they generally collapse to a globule via a local collapse process. The copolymer chains containing 1,2-disubstituted cycloparaffin structures form more kinks and take shorter time to totally collapse into a single globule than the others. Moreover, from the morphology of the crystal structures after annealing it is found that the copolymer chains containing 1,2-disubstituted cycloparaffin structures can yield more ordered structures with cyclic units rejected to the fold surface. For the copolymer chains containing 1,3- or 1,4-disubstituted cycloparaffin, the lamellar structures are not perfect and some cyclic units are always incorporated in the crystalline phase.     

A facile synthesis of thiosemicarbazides containing the 4-antipyrinyl group under microwave irradiation in solvent-free conditions

A simple, efficient and eco-friendly method for the synthesis of a series of thiosemicarbazides containing 4-antipyrinyl group under microwave irradiation has been reported, no solvent and catalyst was used. Five of them are new compounds.     

Copper-alginates: a biopolymer supported Cu(II) catalyst for 1,3-dipolar cycloaddition of alkynes with azides and oxidative coupling of 2-naphthols and phenols in water

Copper(II) ions immobilized onto a biopolymer (sodium alginate) is an effective heterogeneous catalyst for 1,3-dipolar cycloaddition of alkynes with azides and oxidative coupling of 2-naphthols and phenols in water to afford the 1,4-disubstituted 1,2,3-triazoles and biaryl compounds respectively in good yields. The catalyst was recovered quantitatively by simple filtration and reused for several times without significant loss of activity.     

Palladium supported on amine-functionalized mesoporous silica: Highly efficient phosphine-free catalyst for alkyne–alkyne cross-coupling reaction

An amine-functionalized mesoporous silica SBA-15 supported palladium catalyst was prepared and characterized. For the first time, this supported palladium has been used as an efficient phosphine-free and reusable catalyst for the cross-coupling of haloalkynes with terminal alkynes. A variety of haloalkynes and aromatic/aliphatic terminal alkynes were selectively coupled to afford unsymmetrical 1,4-disubstituted 1,3-diynes in good yields.     

酰氨基硫脲及其杂环衍生物的研究进展

酰氨基硫脲类化合物是一类重要的有机硫化合物,它们不仅是合成多种杂环化合物的有机中间体,而且具有杀菌、杀虫、抗结核、抗癌、徐草及调节植物生长等多种重要的生物活性.介绍了酰氨基硫脲及其杂环衍生物的应用进展及合成方法,同时对该类化合物的广阔开发前景进行了展望.     

The Effect of Annelation on the Colour of 1, 4-Disubstituted Benzoanthraquinone Disperse Dyes

The visible spectra of a series of 1,4-disubstituted benzoanthraquinone dyes in benzene solution has been measured. The position of the absorption maxima of the dyes has been found to be well correlated with a mean ionization potential of the substituent groups. An annelation of anthraquinone dyes in the position of 2, 3 or 6, 7produced a small hypsochromic shift, while 5,6-annelation produced a large bathochromic shift. The additive properties on the absorption maximum of dibenzoanthraquinone dyes were also observed.     

新型含氟聚醚酰亚胺的合成与表征

利用对苯二酚、2-氯-5-硝基三氟甲苯合成得到1,4-双(2-三氟甲基-4-硝基苯氧基)苯,再在钯/炭、水合肼和有机溶剂的作用下,合成得到了1,4-双(2-三氟甲基-4-氨基苯氧基)苯,并对其性能进行了表征,包括其本身的熔点、红外吸收特征等。合成得到的1,4-双(2-三氟甲基-4-氨基苯氧基)苯与4,4'-二氨基二苯醚、2,2-双[4-(3,4-二羧基苯氧基)苯基]丙烷二酐反应,制得了含氟聚醚酰亚胺,并对其性能进行了表征。     

Antioxidants and stabilizers, 81. Transformations of N,N′-diphenyl- and N-phenyl-N′-isopropyl-1,4-benzoquinonediimines on silicagel

Transformations of N,N′-disubstituted 1,4-benzoquinonediimines have been investigated as a means for the elucidation of processes occurring in hydrocarbon polymers stabilized with amine antidegradants and of transformations accompanying the analyses of extracts of aged rubbers. N-Phenyl-N′-isopropyl-1,4-benzoquinonediimine (1b) is quickly hydrolyzed on a silicagel surface, giving rise to N-phenyl-1,4-benzoquinoneimine (3). The hydrolysis of N,N′-diphenyl-1,4-benzoquinonediimine (1a) proceeds more slowly under the same conditions, but the released aniline quickly reacts with the initial (1a), giving rise to N,N′-diphenyl-1,4-phenylenediamine(2a), 2-(phenylamino)-N,N′-diphenyl-1,4-benzoquinonediimine (4) and azophenine (5). The Reaction is catalyzed by the weakly acid surface of silicagel. Compound (4) is readily disproportionated thermally to 1,2,4-tris(phenylamino)-benzene (8) and 2, 10-dihydro-10-phenyl-2-(phenylimino)phenazine (9), even in the absence of a catalyst. A mechanism of the formation of compounds arising in the reaction has been suggested. Diimine (1a) possesses a higher oxidation potential than all the products derived from it, so that it is quickly reduced by these products to (2a). The gradual formation of (2a) may explain the retardation effects of (1a) in the autooxidation of hydrocarbon substrates.     

Inhibitive effect of FA derivatives on mild steel corrosion in the presence of formic acid

The influence of selected long-chain FA hydrazides and thiosemicarbazides on the corrosion inhibition of mild steel in the presence of 20% formic acid was studied. The inhibition efficiency of these compounds varied with concentration, temperature, and immersion time. All the FA derivatives in the formic acid solution followed Temkin's adsorption isotherm. The activation energies and free energies of adsorption of all the hydrazides and thiosemicarbazides also were calculated. Potentiodynamic polarization studies indicated that all the tested compounds were of mixed type. Electrochemical impedance spectroscopy was also used to investigate the mechanism of corrosion inhibition.