用8—氨基喹啉高选择性分光光度法测定痕量锇的研究

研究了用８－氨基喹啉在ｐＨ３．６２的ＨＡｃ－ＮａＡｃ缓冲溶液中测定痕量Ｏｓ（Ⅳ）的分光光度法。常用的非贵金属和贵金属离子不干扰测定，并且选择性较好。Ｏｓ（Ⅳ）与８－氨基喹啉的组成比为１：３，表观摩尔吸光系数ε６００＝１．３×１０＾５Ｌ／ｍｏｌ·ｃｍ。在０～１０μｇ／１０ｍＬ范围内符合比耳定律。合成样品分析结果良好。     

铂－锇共显色衍生配合物的高效液相色谱研究

研究了Ｏｓ（Ⅱ）和４，４’二（二乙氨基）苯硫酮与Ｐｔ（Ⅱ）共显色所衍生的配合物，于ＮｕｃｌｅｏｓｉｌＣ＿８柱上，用含３×１０￣（－３）ｍｏｌ／ＬＤＬ－樟脑－１０－磺酸和０．０２ｍｏｌ／ＬＨＡｃ－ＮａＡｃ（ｐＨ３．５）的乙腈－丙酮－水（７２：５：２３，Ｖ／Ｖ）作流动相（１．０ｍＬ／ｍｉｎ）分离并检测。线性范围为０．２～４．０μｇ／ｍＬＰｔ；检测限为１．０ｎｇＰｔ。此方法已应用于抗癌药物顺铂和卡铂的分析。     

铟(Ⅲ)-7-(1-苯偶氮)-8-羟基喹啉-5-磺酸钠的配位吸附波及其应用

在ｐＨ４．５的 ０．０１５ ｍｏｌ／Ｌ ＨＡｃ－ＮａＡｃ介质中，Ｉｎ铟（Ⅲ）－７－（１－苯偶氮）－８－羟基喹啉－５－磺酸钠（ＢＱ）在滴汞电极上于－０．６６５－０．７０ Ｖ（ｖｓ．ＳＣＥ）电位处得到络合物的吸附还原波，其一阶导数峰电流Ｉ＇ｐ与Ｉｎ（Ⅲ）浓度在４．０× １０~（－８）～３．５ × １０~（－６）ｍｏｌ／Ｌ范围内呈良好的线性关系，检测限为１．６ × １０~（－８）ｍｏｌ／Ｌ Ｉｎ（Ⅲ）．应用该法测定了铅粉和氢氧化铝样品中的微量铟，结果令人满意。对电极反应机理进行了探讨。     

2—（5—溴—2—吡啶偶氮）—5—二甲氨基苯胺与铂（Ⅳ）显色反应及其应用

１引言目前，已有多种杂环偶氮类试剂测定铂的报道，但其在显色灵敏度等方面大多还不理想。本文系统研究了２－（５－溴－２－吡啶偶氮）－５－二甲氨基苯胺（５－Ｂｒ－ＰＡＤＭＡ）与Ｐｔ（Ⅳ）的显色反应，结果表明，在ｐＨ４．０～６．０的酸度范围内，在加热条件下铂（Ⅳ）与试剂形成紫红色络合物。该络合物在１．６ｍｏｌ／Ｌ高氯酸溶液中转变为另一型体绿蓝色络合物，表观摩尔吸光系数ε＝８．３×１０４Ｌ·ｍｏｌ－１·ｃｍ－１，大多数常见金属离子及Ａｕ３＋、Ａｇ＋等贵金属离子在一定范围内对测定无干扰。在ＥＤＴＡ存在下，可…     

亚硝酸根—巯基乙酸—钴（Ⅱ）络合物的极谱吸附波研究

提出了一个测定痕量亚硝酸根的极谱吸附波新体系．在含有巯基乙酸（ＴＧＡ）和钻．（Ⅱ）的 ｐＨ ４．４的 Ｈ２ＳＯ４－ＮａＡｃ介质中，得到一灵敏的亚硝酸根络合物单扫极谱吸附波，峰电位为－０．７５ Ｖ（ｖｓ．ＳＣＥ）．峰电位与亚硝酸根浓度在１．１× １０－３－８．７×１０－６ｍｏｌ／Ｌ范围内呈线性关系．检出限为 ５． ５×１０－９ ｍｏｌ／Ｌ．本法简便快速，选择性好，用于水样和食品中痕量ＮＯ-２的测定，结果满意。     

碘酸钾存在下极谱催化波法测定陈皮甙

基于陈皮甙在ＫＩＯ３存在下产生的极谱催化波，拟定了测定陈皮甙的新方法。在 ０．５５ ｍｏｌ／Ｌ ＨＡｃ－０．０１ｍｏｌ／Ｌ　ＮａＡｃ（ｐＨ ４．００±０．０５）－１．０×１０～（－３）ｍｏｌ／Ｌ ＫＩＯ３缓冲溶液中，陈皮甙催化波的峰电位为－１．３５ Ｖ（ｖｓ，ＳＣＥ），它的一阶导数峰峰电流与陈皮甙浓度在２．６ × １０～（－７）～２．６ × １０～（－６）ｍｏｌ／Ｌ范围内呈线性关系（ｒ＝０．９９７０，ｎ＝６）。本方法比现有的电化学方法灵敏度高一个数量级。可用于直接测定中草药贯众水提液中陈皮甙含量。     

铟（Ⅲ）—2—硫基苯骈噻唑—7—碘—8—羟基喹啉—5—磺酸三元络合物吸附波研究

在ＨＣｌ－ＮａＡｃ介质（ｐＨ２．５）中，用单扫示波极谱法可获得高灵敏的Ｉｎ（Ⅲ）－２－巯基苯骈噻唑（ＭＢＴ）－７－碘－８－羟基喹啉－５－磺酸（Ｆｅｒｒｏｎ）三元络合物吸附波，峰电位在一－０．６４Ｖ（ｖｓ．ＳＣＥ），峰电流与铟浓度在７．０×１０＾－１０ｍｏｌ／Ｌ～８．８×１０＾－７ｍｏｌ／Ｌ之间呈线性关系，检出限可达３．０×１０＾－１０ｍｏｌ／Ｌ，测得电活性络合物的组成为Ｉｎ（Ⅲ）：ＭＢＴ：１∶１∶     

钛(Ⅳ)-5-Br-PADAP-NaClO_3体系极谱吸附催化波的研究

２－（５－溴－２－吡啶偶氮）－５－二乙氨基苯酚（５－Ｂｒ－ＰＡＤＡＰ）在极谱和伏安分析中的应用已有一些报道。陈林林等曾经研究过Ｔｉ（Ⅳ）－５－Ｂｒ－ＰＡＤＡＰ络合物在稀Ｈ２ＳＯ４－Ｈ２Ｃ２Ｏ４溶液中的极谱行为,但灵敏度不高（１．０×１０－７ｍｏｌ／Ｌ）。我们发现,在ｐＨ４．１左右的ＨＡｃ－ＮａＡｃ底液中,Ｔｉ（Ⅳ）－５－Ｂｒ－ＰＡＤＡＰ－ＮａＣｌＯ３体系产生一灵敏的极谱吸附催化波,二次导数峰电位在－０．８６Ｖ（ｖｓ．ＳＣＥ）左右,波形良好,波高稳定,检测限可达４×１０－１０ｍｏｌ／Ｌ。１　实验部…     

4－氨基－3，5－二甲基－1，2，4－三唑水杨亚胺合铜〔Ⅱ〕配合物合成及其单晶结构

４－氨基－３，５－二甲基－１，２，４－三唑（ＴＺ）与水杨醛缩合形成４－（邻羟苯基亚甲基）－亚胺－３，５－二甲基－１，２，４－三唑Ｓｃｈｉｆｆ碱（ＳＡＴＺ），该Ｓｃｈｉｆｆ碱与Ｃｕ（ＣｌＯ＿４）＿２·６Ｈ＿２Ｏ形成配合物Ｃｕ（ｓａｔｚ）＿２·６Ｈ＿２Ｏ，分子式为Ｃ＿（２２）Ｈ＿（２２）ＣｕＮ＿８Ｏ＿２·６Ｈ＿２Ｏ。经Ｘ射线晶体结构分析表明，晶体属于单斜晶系，空间群Ｐ２＿１／ｃ，Ｚ＝２，α＝８．２０２（１），ｂ＝１９．５６９（４），ｃ＝８．９７２（８）Ａ，β＝１０７．７２°（２），Ｖ＝１３７１．８（５）Ａ３，Ｄｃ＝１．４６ｇ／ｃｍ￣３，μ＝０．８５３ｍｍ￣（－１），Ｆ（０００）＝６３０，Ｒ＝０．０５１，Ｒ＿ｗ＝０．０６２。分子中２个偶氮甲碱（－Ｃ＝Ｎ－）中　　　的Ｎ原子及２个酚氧原子与中心Ｃｕ原子形成规则的菱形平面结构。     

双臂套索冠醚双核铜（II）配合物的磁性质研究

测定了双臂套索冠醚双核铜（Ⅱ）配合物［Ｃｕ２Ｌ（ＯＨ）］（ＣｌＯ４）３Ｍｅ２ＣＯ（Ｌ－Ｎ，Ｎ＇－二（８－喹啉甲基）－１，４，１０，１３－四氧－７，１６－二氮环八环）的变温磁化率（４￣３００Ｋ），所加场强为５．０×１０＾５Ａ／ｍ，拟合了变温磁化率数据，得到Ｊ＝－２７９．４ｃｍ＾－２；加上分子场校正后，得Ｊ＝－２５７．７ｃｍ＾－１，Ｚｊ＇＝－３０．１ｃｍ＾－１。拟合结果表明，分子间存在反铁磁性交换作用     

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%.     

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.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Copper catalyzed/mediated synthetic methodology for ebselen and related isoselenazolones

Scope of the copper catalyzed/mediated selenium-nitrogen coupling reaction has been studied for the synthesis of isoselenazolones. It is noticed that the 2-chloro, 2-bromo-, and 2-iodo-aryl amides substrates can be exploited in the selenium-nitrogen coupling reaction by employing 25-100 mol % of CuI/1,10-phenanthroline (L) and potassium carbonate as a base in DMF. Furthermore, electron rich 2-chloro-arylamides also underwent selenium-nitrogen coupling reaction to give biologically important selenium-nitrogen heterocycles. Also, copper-catalyzed selenium-nitrogen coupling reaction has been meticulously applied for the synthesis of diaryl diselenides having methoxy, amine, and amide functionality from respective aryl iodides in the presence of stoichiometric amount of succinimide as an external Se-N coupling partner.     

Knoevenagel condensation catalyzed by novel Nmm-based ionic liquids in water

A series of novel N-methyl morpholine (Nmm) based ionic liquids with 1,2-propanediol group were synthesized and used as catalysts for Knoevenagel condensation at room temperature in water. Under the effect of the catalyst, various aldehydes or aliphatic ketones could react with a wide range of activated methylene compounds well, including malononitrile, alkyl cyanoacetate, cyanoacetamide, β-diketone, barbituric acid, 2-arylacetonitrile and thiazolidinedione. Furthermore, most of the products could be separated just by filtrating and washing with water. Additionally, the catalyst is recyclable and applicable for the large-scale synthesis.     

Construction of polyheterocyclic spirotetrahydrothiophene derivatives via sulfa-Michael/aldol cascade reaction

A series of polyheterocyclic spirotetrahydrothiophene derivatives were obtained in moderate to excellent yields via a catalyst-free sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 under mild conditions. We also present the first asymmetric sulfa-Michael/aldol cascade reaction of chalcones 1 and commercially available 1,4-dithiane-2,5-diol 2 with moderate to good enantioselectivities catalyzed by readily available chiral phase-transfer catalysts (PTCs).     

Suzuki-Miyaura reactions of the soluble guanylate cyclase inhibitor NS2028: a non-product specific route to C-8 substituted analogues

Both soluble guanylate cyclase (sGC) inhibitors ODQ 1 and NS2028 2 are synthesized via improved protocols. In the former case treating 3,4-dihydroquinoxalin-2(1H)-one oxime 8, which can be prepared in two steps from 1,2-benzenediamine, with 1,1′-carbonyldiimidazole (CDI) gives the dihydro-ODQ 10 that in the presence of KMnO₄ oxidises to give ODQ 1 in an overall yield of 46% starting from 1,2-benzenediamine. In the latter case, the synthesis affords NS2028 2 from 2-amino-4-bromophenol 3 in three steps with an overall yield of 85% and avoids the need for chromatography. Furthermore, Suzuki-Miyaura reaction conditions are described that enable the preparation of 8-aryl and 8-heteroaryl derivatives of NS2028 directly from NS2028 2. Finally, demethylation of the 8-(methoxyphenyl) substituted analogues afforded the 8-(hydroxyphenyl) derivatives 40-42. All new products are fully characterised.