以聚氯乙烯-双硫腙-铜络合物为载体的长寿命硫氰酸根离子选择电极

报道了以PVG-双硫腙（DTZ）-Cu（Ⅱ）,PVC-DTZ-Cu（Ⅰ）为载体制备了性能良好的SCN-离子电极,其选择性次序为SCN~-》ClO_4~->Sal~-》NO_3~-~Cl~->PO_4~(2-)。16℃时,膜组成为PVC－DTZ-Cu（Ⅰ）：PVC：邻硝基苯基辛醚（o-NPOE）＝12∶22∶66的SCN~-离子电极,在0．02mol/LHCl体系中,在1×10~(-2)~5×10~(－6)mol/LSCN~-浓度范围呈能斯特响应,斜率为58±2mV/dec,检测限为2×10~(-6)mol/L;膜组成为PVC-DTZ-Cu（Ⅱ）∶PVC∶o-NPOE∶四苯硼酸钾（KTPB）为8∶22∶55∶15的电极,在0．01mol/LHAc-NaAc缓冲体系中,在10~(-2)~2×10~(-6)mol/LSCN~-浓度范围呈线性响应,斜率为54∶1mV/dec,检测限为8×10~(－7)mol/L.研究了阴离子与载体作用的机理,表明SCN~-与载体中铜原子直接作用。电极应用于废水中SCN~-的测定,结果令人满意。     

全固态曲马多选择电极的研制与应用

报道了一种以曲马多碘化物与碘化铋的分子缔合物为电活性物的新型全固态选择电极,电极的能斯特响应范围为6.3×10~(-2)～3.2×10~(-5)mol·L~(-1),斜率为50mV/pC,检测限为0.6×10~(-5)mol·L~(-1)。此电极响应迅速,重现性好。用此电极以标准曲线法对注射液中的曲马多进行了测定,结果与紫外分光光度法相符。     

聚氯乙烯膜苯海拉明选择电极的研制与应用

报道了一种以苯海拉明碘化物与碘化铋形成的分子缔合物为电活性物的新型PVC膜苯海拉明选择电极。电极的线性响应范围为 1 0× 10 -1～ 2 .6× 10 -5mol/L ;级差为 4 8mV/pC ;检出限为 1 9× 10 -5mol/L。该电极响应迅速 ,重现性好 ,用此电极以校准曲线法对片剂中的苯海拉明进行了测定 ,此法简便 ,结果与药典法相符     

PVC膜黄连素离子选择电极的研制及应用

本文报道一种以黄连素溴汞酸盐为电活性物的涂碳型PVC膜黄连素离子选择电极,其线性响应范国为10~(-3)—5×10~(-7)mol/L,级差56mV(23℃),检测限为2.2×10~(-7)mol/L。应用此电极测定黄连素药片的含量,方法简单、快速,结果与药典法相符。     

聚氯乙烯膜依诺沙星选择电极的研制与应用

以盐酸依诺沙星与四苯硼酸盐生成的分子缔合物制成新型PVC膜依诺沙星选择电极,应用于依诺沙星药片的含量测定。在pH 2.2～6.5范围内,电极的能斯特响应范围为5.0×10~(-5)～1.0×10~(-2)mol/L,斜率为58.0mV/pc,检出限为4.2×10~(-6)mol/L。该电极响应速度快,重现性好。3次测定的平均回收率为97.5％,RSD为1.0％,结果与紫外分光光度法基本一致。     

新型涂碳式双嘧达莫选择电极的研制与应用

报道了一种以双嘧达莫与碘化铋形成的缔合物为电活性物的新型涂碳式PVC膜双嘧达莫选择电极,测定了双嘧达莫片的含量。电极线性响应范围为1.0×10-2~2.2×10-5mol/L,级差电位为48 mV/pc,检出限为1.8×10-5mol/L。该电极响应迅速,重现性好,分析结果与药典法相符。     

聚氯乙烯膜普鲁卡因选择电极的研制与应用

研制了一种以普鲁卡因碘化物与碘化铋形成的缔合物为电活性物质的PVC(聚氯乙烯 )膜普鲁卡因选择电极 ,测定了普鲁卡因注射液的含量 ;电极的线性响应范围1.0×10 -1～6.3×10 -5mol/L,级差电位为45mV/pc ,检出限为3.4×10-5 mol/L ;该电极响应迅速 ,测定结果与药典法相符     

基于Ag/AgCl丝双涂膜曲马多离子选择电极的研制与应用

以Ag/AgCl丝为基体依次外涂含0.1mol/LKCl的琼脂凝胶膜及含四苯硼 曲马多缔合物的PVC膜,制备了一种双涂膜曲马多离子选择电极。该电极的线性范围为2.5×10-5～1.0×10-2mol/L,斜率为57.3mV/pc,检出限为1.6×10-5mol/L,性能稳定,体积微小,能用于盐酸曲马多制剂的含量测定。     

利眠宁-碘铋酸盐修饰碳糊电极的制作及应用

以利眠宁与硝酸铋(物质的量的比为1∶1)的分子缔合物作为电活性物质,研制了利眠宁-碘铋酸盐修饰碳糊电极,该电极对溶液中的利眠宁有良好的线性响应,响应斜率为-58.8 mV/pc,线性范围为6.0×10~(-5)～1.0×10~(-1)mol/L,达4个数量级,检出限为1.0×10~(-5)mol/L,RSD为1.0％～1.4％,加标回收率为98.0％～102％。该电极可用于利眠宁片中利眠宁含量的测定。     

凝胶醌氢醌PVC涂膜曲马多选择电极的研制

研制了一种新型PVC涂膜曲马多选择电极,该电极以凝胶醌氢醌电极为内参比电极,外涂含曲马多-四苯硼离子缔合物的PVC膜构建而成。其Nernst响应范围为4.0×10-5~1.0×10-2mol·L-1,斜率为57.4mV/pc(25℃),检出限为1.9×10-5mol·L-1,适用的pH范围为2~8。电极性能稳定,用于片剂中盐酸曲马多含量测定,回收率为96%~102%,结果与中国药典法一致。     

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%.     

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.     

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.     

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.