新西佛碱3.5—二溴水杨醛缩氨基硫脲的合成及其在荧光滴定中的应用

本文研究了新西佛碱３．５－二溴水杨醛缩氨基硫脲（简称３．５－ＤＢＳＴＳ）的合成，及基为一种新荧光滴定指示剂，应用于有色溶液中酸碱滴定的条件，建立了一种简便，准确，快速测定有色溶液中酸碱浓度的新方法，用于有色饮料中酸含量的测定，结果满意，指示剂发光的ｐＨ突跃范围为７．４８－９．７２，λｅｘ＝５００ｎｍ。     

5′—硝基水杨基荧光酮荧光熄灭法测定微量钨

本文基于Ｗ（Ⅵ）－５′－硝基水杨基荧光酮（５′－Ｎ－ＳＡＦ）－Ｔｗｅｅｎ－８０体系的荧光熄来效应，提出一种测定微量钨的荧光方法，在０．２～１．０ｍｏｌ／Ｌ的硫酸介质中，在Ｔｗｅｅｎ－８０存在下，５′－Ｎ－ＳＡＦ存在两个激发峰，其激发波分别为λｅｘ１＝４７５ｎｍ，λｅｘ２＝５０５ｎｍ发射波长为λｅｍ＝５２５ｎｍ。Ｗ（Ⅵ）与５′－Ｎ－ＳＡＦ形成１：３的配合物，钨浓度在每２５ｍＬ０．２５～２．５μｇ范围     

二溴羟基苯基荧光酮荧光猝灭法测定Br~－

本文报道了以二溴羟基苯基荧光酮（ＤＢＨ－ＰＦ）为指示剂，在阳离子表面活性剂ＣＰＣ存在下荧光猝灭间接测定Ｂｒ￣－的新方法。在０．６ｍｏｌ／ＬＨ＿２ＳＯ＿４介质中，Ｂｒ￣－和ＢｒＯ反应生成Ｂｒ＿２，Ｂｒ＿２与ＤＢＨ－ＰＦ（λ＿（ｅｘ）＝４９５ｎｍ，λ＿（ｅｍ）＝５２０ｎｍ）生成红色化合物，使体系荧光猝灭。Ｂｒ￣－含量在０．２５～６．２５μｇ／２５ｍＬ范围内有良好的线性关系，检测限为０．２５μｇ／２５ｍＬ。该法灵敏度高，选择性好，用于合成海水样品中Ｂｒ￣－的测定，结果满意。     

荧光光度法测定环境水中微量甲基对硫磷

研究了荧光分光光度法测定环境水中甲基对硫磷的一。在吲哚丙酮溶液０．２５％，过硼酸钠溶液０．２５％溶液中，温度５℃、λｅｘ／λｅｍ＝４１０ｎｍ／４９０ｎｍ，检出限５．０（５．２）μｇ／Ｌ，线性范围０－２．０（２．６）ｍｇ／Ｌ，回收率达９８－１０２％，结果满意。     

邻菲罗啉－水杨基荧光酮荧光熄灭新体系测定银的研究

在聚乙烯醇（ＰＶＡ）存在下Ａｇ（Ｉ）与水杨基荧光酮（ＳＡＦ）及邻菲罗啉（ｏ－ｐｈｅｎ）形成异配位体配合物使水杨基荧光酮的荧光熄灭。在ｐＨ６．４～７．３，ＨＡｃ－ＮＨ＿４Ａｃ或ＮＨ＿３·Ｈ＿２Ｏ－ＮＨ＿４Ａｃ的介质中，λ＿（ｅｘ）＝４００ｎｍ，λ＿（ｅｍ）＝５１０ｎｍ，体系的荧光熄灭程度最大，线性范围为０～０．６ｍｇ／Ｌ，检出限为０．００９ｍｇ／Ｌ。方法用于阳极泥中银的测定，结果满意。     

新荧光试剂3－对甲苯基－5－（2’－羧基苯偶氮）绕丹宁的合成及荧光光度法测定蚕丝制品中痕量铜的研究

本文报道了新荧光试剂３－对甲苯基－５－（２’－羧基苯偶氨）绕丹宁（ＰＭ－ＰＲＡＣＰ）的合成。用元素分析、红外光谱、核磁共振氢谱和质谱确证了其结构，研究了其荧光性质。在ｐＨ５．６时，该试剂与Ｃｕ￣（２＋）形成稳定的荧光螯合物，且在λ＿（ｅｘ）／λ＿（ｅｍ）＝３０５ｎｍ／４０５ｎｍ产生强烈荧光。其荧光强度与Ｃｕ￣（２＋）的浓度在０～１．６μｇ／２５ｍＬ范围内呈线性关系，检测限为５×１０￣（－４）μｇ／ｇ。已用于痕量铜（Ⅱ）的荧光分光光度法测定。测定了蚕茧、蚕丝和丝绸中的痕量铜，结果满意。     

5''''-硝基水杨基荧光酮荧光熄灭法测定微量钨

本文基于Ｗ（Ⅵ）－５′－硝基水杨基荧光酮（５′－Ｎ－ＳＡＦ）－Ｔｗｅｅｎ－８０体系的荧光熄灭效应，提出一种测定微量钨的新荧光方法。在０．２～１．０ｍｏｌ／Ｌ的硫酸介质中，在Ｔｗｅｅｎ－８０存在下，５′－Ｎ－ＳＡＦ存在两个激发峰，其激发波分别为λｅｘ１＝４７５ｎｍ，λｅｘ２＝５０５ｎｍ，发射波长为λｅｍ＝５２５ｎｍ。Ｗ（Ⅵ）与５′－Ｎ－ＳＡＦ形成１∶３的配合物。钨浓度在每２５ｍＬ０．２５～２．５μｇ范围内呈线性关系，检测限为每２５ｍＬ０．２５μｇ。本法灵敏度高，选择性好，不经分离可直接测定合金钢中的钨，结果满意。     

［Li（THF）_4］［（t－BuCp）Yb（NPh_2）_3］的合成及晶体结

合成了标题配合物［Ｌｉ（ＴＨＦ）＿４］［ｔ－ＢｕＣｐ）Ｙｂ（ＮＰｈ＿２）＿３］，经元素分析、红外光谱表征，并测定了其晶体结构。配合物属正交晶系，Ｐｂｃａ空间群，晶体学参数ａ＝１．４５１５（５），ｂ＝２．２８３３（５），ｃ＝３．３５５４（６）ｎｍ；Ｖ＝１１．１２０９（５）ｎｍ￣３；Ｄ＿ｃ＝１．３１ｇ·ｃｍ￣＿（－３）；Ｆ（０００）＝４４．２３，Ｚ＝８。最后一致性因子Ｒ＝０．０４７，Ｒ＿ｗ＝０．０４５，平均Ｙｂ－Ｎ键长是０．２２６４（９）ｎｍ。     

荧光猝灭法测定微量氟的研究

建立了氟的铝－钙指示剂络合物荧光猝灭测定法。本法λｅｘ＝５７０ｎｍ，λｅｍ＝６００ｎｍ，线性范围为５～１６０ｎｇ／ｍＬＦ＾－。对５ｎｇ／ｍｌＦ＾－重复１１次测定结果的相对标准偏差为２．４％，可直接用于温泉水中氟的测定。     

贵金属冶金物料中微量钯、铂、铑的双波长分光光度法同时测定的研究

本文提出了用二苄基二硫代乙二酰胺（ＤｂＤＯ）为显色剂分光光度测定铑的方法，并进一步研究了该试剂与钯、铂的反应，从而建立了可在一个试样中同时测定该三元素的方法。在２～３ｍｏｌ／ＬＨＣ１溶液中，钯与ＤｂＤＯ在室温显色，用氯仿萃取并用８．４ｍｏｌ／ＬＨＣ１振荡有机相，然后在４５４ｎｍ测定。在萃余液中加入ＳｎＣｌ＿２，并在沸水浴中加热，使铂、铑的ＤｂＤＯ络合物生成，再用氯仿萃取，８．４ｍｏｌ／ＬＨＣ１振荡有机相，以双波长分光光度法同时测定。其中铂用双波长系数倍率法（λ′＿２＝５２１ｎｍ，λ′＿１＝５００ｎｍ，Ｋ＝２．５６３），铑用双波长等吸收波长法（λ＿２＝４００ｎｍ，λ＿１＝５４６ｎｍ）。铂和铑的含量为１：５或５：１时互不干扰。     

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.     

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.     

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.     

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.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

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.     

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.     

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.