钛—安替比林偶氮连苯三酚—抗坏血酸—苄基十四烷基二甲基氯化铵四…

本利用自制的安替比林偶氮连苯三酚（ＡｎＡＰ）研究了Ｔｉ－ＡｎＡＰ－抗坏血酸（Ｖｃ）－苄基十四烷基二甲基氯化铵（Ｚｅｐｈ）四元络合体系。结果表明，四元络合体系在ｐＨ５．０－６．５范围以测钛具有较高灵敏度，最大吸收波长４７５ｎｍ处的表观摩尔吸光系数为６．０３×１０＾４Ｌ．ｍｏｌ＾－＾１．ｃｍ＾－＾１。钛量在０－１２μｇ／２５ｍＬ范围内服从比尔定律。加入乙酰丙酮等掩蔽剂后，此体系可用于某些矿石，土壤等     

Ti（Ⅳ）－F~－－邻硝基苯基荧光酮－氯化十六烷基吡啶四元体系显色反应的研究

本文较详细研究了在Ｈ＿２ＳＯ＿４介质中，Ｔｉ（Ⅳ）－Ｆ￣－－ｏ－ＮＰＦ－ＣＰＣ体系水相光度法测定痕量钛的新方法。四元体系的最大吸收峰在５６５ｎｍ处，表观摩尔吸光系数为２．１×１０￣５Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１），Ｓａｎｄｅｌｌ灵敏度为２．２８×１０￣（－４）μｇＴｉ／ｃｍ￣２。钛含量在０～４μｇ／２５ｍＬ范围内遵守比尔定律。方法用于土壤、粮食、牧草、蔬菜和中草药中钛的测定，结果满意。     

微乳液的增敏作用研究──Ni（Ⅱ）－5－Br－PADAP的分光光度法测定

以含水量８０％的阴离子型ＳＤＳ／ｎ－Ｃ＿（５）Ｈ＿（１１）ＯＨ／ｎ－Ｃ＿（７）Ｈ＿１６／Ｈ＿（２）Ｏ微乳液为介质，进行了Ｎｉ（Ⅱ）－５－Ｂｒ－ＰＡＤＡＰ的分光光度研究，其表观摩尔吸光系数为１．１３×１０￣５Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１），与相应含水量的ＳＤＳ胶束介质比较，测定的灵敏度显著提高（后者为７．５×１０￣４Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１）），样品分析结果令人满意。     

Fe（Ⅲ）－TEA－5－Br－PADAP－H_2O_2体系中催化波的研究及其应

在０．２ｍｏｌ·Ｌ￣（－１）ＮＨ＿４Ｃｌ－ＮＨ＿３·Ｈ＿２Ｏ底液中，（ｐＨ为９．２６），得到一个极为灵敏的Ｆｅ（Ⅲ）－ＴＥＡ－５－Ｂｒ－ＰＡＤＡＰ－Ｈ＿２Ｏ＿２配合吸附催化波，其峰电位为－０．７１Ｖ（ｖｓ．ＳＣＥ）。铁浓度在１．８×１０￣（－１０）～５．４×１０￣（－６）ｍｏｌ·Ｌ￣（－１）范围内与二阶导数波高呈线性关系。对该极谱波的性质进行了研究，证明是一种配合吸附催化波，并成功地应用于各类水样，钒催化剂中微量或痕量铁的测定。     

四元配合物吸光光度法测定铝的研究

提出了在乙酸钠－乙酸介质中,利用Ａｌ－ＥＧＴＡ－ＰＲ－ＣＰＢ四元体系测定铝的新方法。试验表明乙二醇二乙醚二氨基四乙酸（ＥＧＴＡ）,铝,邻苯三酚红（ＰＲ）,溴化十六烷基吡啶（ＣＰＢ）可迅速反应生成四元蓝色配合物Ａｌ·ＥＧＴＡ·ＰＲ３·ＣＰＢ１２,可用于痕量铝的测定,ε＝１．１×１０＾５Ｌ·ｍｏｌ＾－１·ｃｍ＾－１,ＲＳＤ为５．８％（ｎ＝６）。加标回收率１０１．７％￣１０５．０％,实测水和化学试剂中痕     

新显色剂2－（5－硝基－2－吡啶偶氮）－5－二甲氨基苯胺与钯显色反应的研究及其应用

用新合成的偶氮试剂２－（５－硝基－２－吡啶偶氮）－５－二甲氨基苯胺（５－ＮＯ＿２－ＰＡＤＭＡ）研究了光度法测定他的反应条件。结果表明，在０．４５～１．２ｍｏｌ／Ｌ盐酸介质中，钯与试剂形成稳定的蓝色配合物，其最大吸收波长位于６２１ｎｍ处，表观摩尔吸收系数为９．４×１０￣４Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１），配合成的组成为Ｐｄ：５－ＮＯ＿２－ＰＡＤＭＡ＝１：２，钯浓度在０～１０μｇ／１０ｍＬ范围内符合比尔定律。本方法是目前测定钯的高灵敏度和高选择性体系之一。用于含钯分子筛及二次合金管理样－８８中微量钯的测定，结果满意。     

5，10，15，20－四（3－溴－4－磺酸苯基）卟啉光度法测定痕量铜的研究

本文研究了新水溶性卟啉试剂５，１０，１５，２０－四（３－溴－４－磺酸苯基）卟啉［Ｔ（３－ＢｒＰ）ＰＳ＿４与铜的显色反应。在ｐＨ３，铜与５，１０，１５，２０－四（３－溴－４－磺酸苯基）卟啉形成１：１的稳定配合物。此配合物的最大吸收波长位于４１２．８ｎｍ，摩尔吸光系数为２．６１×１０￣５Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１）。铜量在０～３．０μｇ／２５ｍＬ范围内符合比尔定律，工作曲线回归方程为ｙ＝０．００９４３、＋０．１６７ｘ，相关系数为ｒ＝０．９９９７。方法有较高的灵敏度和较好的选择性，直接用于大米和茶叶中痕量铜的测定，结果与ＡＡＳ法一致。     

13，15－苯并－1，4，8，11－四硫杂环十六烷及其钯（Ⅱ）络合物的合成和结构测定

报导了硫冠醚１３，１５－苯并－１，４，８，１１－四硫杂环十六烷（ＴＴｍＸ）及其钯（Ⅱ）络合物（ＴＴｍＸ·２ＰｄＣ＿ｌ２）的合成，并通过Ｘ射线衍射分析测定了该配体及其络合物的晶体结构。ＴＴｍＸ属单斜晶系，Ｐ＿２＿１／ｎ空间群，晶胞参数：ａ＝９．５４５（３），ｂ＝９．０６５（１），ｃ＝１９．６４５（３）Ａ，β＝９５．３８（１）°，Ｖ＝１６９２．３（５）Ａ￣３，Ｚ＝４，μ＝５．２６ｃｍ￣（－１），Ｄｃ＝１．３０ｇ·ｃｍ￣（－３）。ＴＴｍＸ·２ＰｄＣｌ＿２属正文晶系，Ｐｂｃａ空间群，晶胞参数：ａ＝１１．３９２（２），ｂ＝１４．５８０（４），ｃ＝２７．１４６（９）Ａ，β＝９０．００（０）°，Ｖ＝４５０９（２）Ａ￣３，Ｚ＝８，μ＝２４．１２ｃｍ￣（－１），Ｄｃ＝２．０２ｇ·ｃｍ￣（－３）。     

Cr（Ⅵ）－PF－CDMAA显色反应及其应用

本文研究了铬（Ⅵ）－苯基荧光酮（ＰＦ）－＋六烷基二甲基氨基乙酸（ＣＤＭＡＡ）体系的分光光度特性和最适宜的显色条件。在两性表面活性剂ＣＤＭＡＡ存在下，于ｐＨ５．５～７．４的缓冲介质中铬（Ⅵ）与ｐＦ形成１：３的紫红色配合物，显色体系在５７６ｎｍ处有最大吸收，其摩尔吸光系数为１．４６×１０￣５Ｌ·ｍｏｌ￣（－１）＊ｃｍ￣（－１），铬（Ⅵ）含量在０～８．０μｇ／２５ｍＬ范围内符合比尔定律，变异系数为１．０３％～４．３３％。方法简便，灵敏度高，精密度和准确度好，在混合掩蔽剂存在下，可直接测定水中铬（Ⅵ）。     

铬（Ⅵ）与5－溴水杨基荧光酮的显色反应及应用

本文研究了Ｃｒ（Ⅳ）与５－溴水杨基荧光酮（５－Ｂｒ－ＳＡＦ）的显色反应。在ｐＨ６．０ＫＨ＿２ＰＯ＿４－ＮａＯＨｉＬ冲溶液中，Ｃｒ（Ⅳ）与５－Ｂｒ－ＳＡＦ、ＣＴＭＡＢ形式稳定的三元络合物，其最大吸收波长为５７２ｎｍ，表现摩尔吸光系数为１．４２×１０￣５Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１）。Ｃｒ（Ⅳ）浓度在０～２．５μｇ／１０ｍＬ间服从比耳定律。用此法测定了环境水样中微量Ｃｒ（Ⅳ），获得满意结果。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Microwave-assisted copper-catalyzed stereoselective ring expansion of three-membered heterocycles with α-diazo-β-dicarbonyl compounds

Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular S_N2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.