以硅胶G胶片和滤纸作基质氟哌酸的固体基质室温燐光法研究

探讨了氟哌酸的固体基质室温燐光法（ＳＳ－ＲＴＰ）中的基质效应和重原于效应，经聚丙烯酸（ＰＡＡ）处理的硅胶Ｇ胶片做基质测定痕量氟哌酸较滤纸为基质具有检测限低、无需重原子微扰剂，稳定性好等优点。     

固体基质室温燐光猝灭法测定人发和水中痕量汞

基于水杨基荧光酮羧甲基纤维素铅发光分子微球(Pb(CMC)2-THBF)在滤纸基质上可发射强而稳定的室温燐光,由此建立了Pb(CMC)2-THBF固体基质室温燐猝灭测定痕量汞的新方法.Hg2 的含量在2.5~100.0(pg/mL)内与ΔIp值成线性关系,其线性回归方程为ΔIp=12.73 0.4699CHg2 (pg/mL),r=0.9991,检出限为3.2×10-13g/mL.该方法用于人发和水样中痕量汞的测定,结果满意.同时探讨了固体基质室温燐光猝灭测定痕量汞的机理.     

固体基质室温燐光法测定吩噻嗪的研究

本文首次应用国产滤纸作为基质,建立了固体基质室温燐光法(SS-RTP)测定吩噻嗪含量的新方法。应用自制的室温燐光样品架研究了样品干燥的温度,样品干燥的时间、点样时机,重原子KI的浓度对室温燐光强度的影响等实验条件,讨论了卤化钠和卤化钾的重原子效应规律。并发现在不吹N_2除O_2的情况下,也能获得吩壤嗪稳定的RTP信号。吩噻嗪的标准曲线在0.1—150ng,0—10ng和0—1.0ng三个数量级上呈良好的线性关系。     

中草药有效成分葛根素的滤纸表面室温燐光法的研究

选择滤纸作基质，以ＬｉＡｃ作重原子微扰剂，首次成功地建立了测定痕量中草药有效成分葛根素的滤纸基质室温燐光法。本法取样量少（２μＬ），线性范围宽（４．１６～４９９ｎｇ／斑），灵敏度高（检测限为０．１９ｎｇ／斑），操作简便、快速。     

补骨脂素、异补骨脂素的固体表面室温燐光分析法

建立了以滤纸为基质的中草药有效成分补骨脂素、异补骨脂素的固体表面室温燐光 分析法。对影响室温燐光强度的各种因素进行了详细的研究，实验表明，补骨脂素的线性范围 为２×１０－６～２×１０－４ｍｏｌ／Ｌ；检出限为０．４７ｎｇ／斑，异补骨脂素的线性范围为４×１０－６～４×１０－４ｍｏｌ／Ｌ；检出限为０．１７ｎｇ／斑。     

12种嘌呤类化合物的滤纸基质室温燐光法研究

较为详细地研究了１２种嘌呤类化合物以滤纸为基质的室温燐光（ＲＴＰ）光谱特性与分子结构的关系，以及重原子效应和酸度效应对ＲＴＰ的影响。     

用固体基质室温燐光法分析环境样品中多环芳烃的研究

用滤纸基质室温燐光法分析多环芳烃。以醋酸铊TlAc/醋酸铅Pb(Ac)_2(1∶1mol)的乙醇水(50％V/V)溶液为重原子微扰剂,对国产分析滤纸,玻璃纤维滤膜和醋酸纤维滤膜等9种不同的基质材料测定芘的燐光信号强度并进行了比较。对芘、荧蒽、苯并(e)芘、苯并(a)芘、苯并(ghi)芘和晕苯的混合物样品进行了测定。对煤飞灰和燃煤排放物样品中的芘和苯并(a)芘进行了定量分析,并用高效液相色谱法对测定结果进行验证。对芘和苯并(a)芘的检测限分别达到10~(-10)和10~(-9)g数量级。本文还对进一步提高灵敏度的问题进行了讨论。     

罗丹明和荧光素类染料的固体基质室温燐光研究

研究了13种吨染料在滤纸基质上的室温燐光（RTP）性质。发现具有重原子取代基的荧光素本身能有较强的RTP发射。若以Ph（AC）2为重原子微扰剂，则所有染料均能产生不同强度的RTP信号。探讨了取代基对RTP发射的影响，测定了它们的RTP寿命。     

以阴离子交换纤维素膜作基质室温燐光法测定痕量2,6-二氨基嘌呤的研究

本文对2,6-二氨基嘌呤(DAP)在不同的基质上和不同的重原子微扰剂存在下的室温燐光(RTP)强度进行比较,结果表明,NaI-NaAc是有效的重原子体系。适宜的固体基质为阴离子交换纤维素(二乙氨基乙基纤维素)膜(DEAE)和慢速定量滤纸。前者对酸度的变化具有较好的缓冲能力,本文提出了以DEAE为固体基质,测定痕量DAP的RTP法。     

国产滤纸应用于固体基质室温燐光法可行性的考察

本文首次考察了国产滤纸应用于固体表面室温燐光法(SS-RTP)的可行性。研究了国产滤纸的RTP背景,温度及重原子对滤纸RTP背景的影响,观察了滤纸经用DTPA和二氧六圜化学处理后背景值的降低情况,以及在应用国产滤纸作基质潮定吩噻嗪的研究中对方法精密度的影响。还与Whatman №41及S & S两种国外滤纸产品做了比较。实验表明,国产滤纸用于SS-RTP技术是可行的。     

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.