稀土与甘氨酰—L—亮氨酸的配位作用

用ｐＨ电位法测定了生理条件（３７℃，Ｉ＝０．１５ｍｏｌ／Ｌ）和２５℃，Ｉ＝０．１０ｍｏｌ／Ｌ时甘氨酰Ｌ－亮氨酸的质子化常数及其稀土配合物稳定常数。结果表明稀土可与该配体形成１：１配合物，并且配合物稳定性呈现明显“四分组效应”。讨论了钇的位置以及肽键对配合物稳定性的影响。     

配合物的直线自由能关系（ⅩⅤⅡ）──铜（Ⅱ）－二氧四胺大环－α－氨基酸三元混配配合物的稳定性研究

用ｐＨ法在２５．０±０．１℃、Ｉ＝０．１ｍｏｌ／ＬＫＮＯ３条件下研究了铜（Ⅱ）与１２－（２＇－羟基－５取代苄基）－１，４，７，１０－四氮杂环十三烷－１１，１３－二酮－α－氨基酸所形成的竞争性三元混配型配合物的稳定性，测定了该体系的二元、三元配合物的稳定常数，并探讨了大环配体的取代基效应及二元、三元配合物的结构。     

钴（Ⅱ）－5－取代邻菲罗啉－α－氨基酸三元配合物的稳定性研究

本文在２５．０±０．１℃，Ｉ＝０．１ｍｏｌ·ｄｍ（－３）ＫＮＯ３存在下，采用ｐＨ法测得了５－取代邻菲罗啉的质子化常数以及钴（Ⅱ）与５－取代邻菲罗啉、α－氨基酸的二元、三元配合物的稳定常数．结果表明三元配合物的稳定性与５－取代邻菲罗啉的质子化常数、取代基常数均存在直线自由能关系．并用三元配合物稳定性的表征值ｌｏｇＫＭ、△ｌｏｇＫ，讨论了三元配合物的稳定性，发现钴（Ⅱ）与配体５－取代邻菲罗啉之间也存在着ｄ－ｐ反馈π键．该π健的强度对三元配合物稳定性有着显著影响．     

配位化学中的直线自由能关系──XX．铜（Ⅱ）－1，4，7，10－四氮杂环十三烧－11，13－二酮－α－氨基酸（5－取代邻菲罗啉）三元配合物的稳定性研究

本文采用ｐＨ法，在２５．０±０．１℃，Ｉ＝０．１ｍｏｌ·ｄｍ－３ＫＮＯ３存在条件下，测定了铜（Ⅱ）－１，４，７，１０－四氮杂环十三烷－１１，１３－二酮－α－氨基酸（５－取代邻菲罗啉）三元配合物的稳定常数，探讨了大环多胺配体与金属离子的配位能力、配位方式、及其在水溶液中铜（Ⅱ）配合物的稳定性，同时也研究了５－取代邻菲罗啉与铜（Ⅱ）之间的ｄ－ｐ反馈π键、取代基的Ｈａｍｍｅｔｔ诱导效应对三元配合物稳定性的影响．     

配合物的直线自由能关系（ⅩⅦ）—铜（Ⅱ）—二氧四胺大环—α—…

用ｐＨ法在２５．０±０．１℃、Ｉ＝０．１ｍｏｌ／Ｌ ＫＮＯ３条件下研究了铜（Ⅱ）与１２－（２＇－羟基－５取代苄基）－１，４，７，１０－四氮杂环十三烷－１１，１３－酮－α－氨基酸所形成的竞争性三元混配型配合物的稳定性，测定了该体系的二元、三元配合物的稳定常数，并探讨了大环配体的取代基效应及二元、三元配合物的结构。     

配合物稳定性和配体酸碱强度之间的直线自由能关系──铜（Ⅱ）、锌（Ⅱ）－芬布芬－α－氨基酸三元配合物体系

在２５±０．１℃，Ｉ＝０．１ｍｏｌ·ｄｍ－３ＫＮＯ３条件下，８０％（ｖ／ｖ）ＤＭＳＯ—Ｈ２Ｏ混合溶剂中，应用ｐＨ法测定了甘氨酸，Ｌ一缬氨酸，Ｌ－异亮氨酸，Ｌ－脯氨酸，Ｌ－丝氨酸，ＤＬ－苯丙氨酸等六种α－氨基酸（缩写为α－ＡＡ，记为Ｂ配体）的酸离解常数，铜（Ⅱ）－α－氨基酸．锌（Ⅱ）－α－氨基酸二元配合物的稳定常数及铜（Ⅱ）－芬布芬－α－氨基酸（芬布芬缩写为Ｆｅｎ，记为Ａ配体）和锌（Ⅱ）－芬布芬－α－氨基酸三元配合物的稳定常数．实验发现，在下面三对参数之间，即ｌｏｇβ１０２与ｐＫ，ｌＯｇβ１１１；与ｐＫ及１０ｇβ１１１与ｌｏｇβ１０２，均存在良好的直线自由能关系．用△ｌｏｇＫＭ和△ｌｏｇβ１１１两个参量描述了三元配合物相对于母体二元配合物的稳定性．讨论了溶剂的性质，配合物分子内配体之间的疏水作用，芳环之间的堆积作用对配合物稳定性的影响．     

稀土－谷氨酸配合物的pH电位法研究

报道了在生理条件（３７℃，Ｉ＝０．１５ｍｏｌ·Ｌ－１ＮａＣｌ）下用ｐＨ电位法对１５种稀土元素与Ｌ－谷氨酸配合物稳定常数的测定结果。玻璃电极校正用ＭＡＧＥＣ程序进行，各体系中配合物物种的选择及其稳定常数的计算用程序ＭＩＮＩＱＵＡＤ－８２Ａ完成，讨论了“四分组效应”及钇的位置。     

铜(Ⅱ)-α-氨基酸(5-取代邻菲咯啉)-L-苏糖酸三元配合物的稳定性研究

在２９８Ｋ，Ｉ＝０．１ｍｏｌ／ＬＫＮＯ３条件下测定了Ｌ－苏糖酸－α－氨基酸（５－取代邻菲咯啉）－铜（Ⅱ）三元配合物的生成常数．实验表明，生物配体α－氨基酸及Ｌ－苏糖酸具有良好的相容性，其三元配合物的稳定性大于相应二元配合物的稳定性．在较宽的ｐＨ值范围内，三元配合物的含量显著大于二元配合物的含量．即Ｌ－苏糖酸能作为金属离子的载体，使金属离子易于与氨基酸或蛋白质结合而被动物吸收利用．α－氨基酸及Ｌ－苏糖酸间的相容性及其三元配合物的稳定常数随α氨基酸的质子化常数及其二元配合物的稳定常数增加而增加，二者间存在良好的直线自由能关系．而在Ｌ－苏糖酸－５－取代邻菲咯啉－铜（Ⅱ）三元配合物中，由于ｄ－ｐ反馈π键的存在，三元配合物的稳定常数随取代邻菲咯啉质子化常数的增加而降低，二者之间也存在良好的直线自由能关系．     

铜（Ⅱ）—α—氨基酸（5—取代邻菲咯啉）—L—苏糖酸三元配合物的稳定性研究

在２９８Ｋ，Ｉ＝０．１ＭＯＬ／ｌＫＮＯ３条件下测定了Ｌ－苏糖酸－α－氨基酸－铜（Ⅱ）三元配合物的生成常数。实验表明，生物配体α－氨基酸及Ｌ＿苏糖酸具有良好的相容性，其三元配合物的稳定性大于相应二元配合物的稳定性。     

[Fe（CN）6]^4—还原trans—[Co（en）2（ImH02]^3＋的电子转移反应 …

在不同的温度下，考察了六氰合铁配阴离子「Ｆｅ（ＣＮ）５」＾４－还原ｔｒａｎｓ－「Ｃｏ（ｅｎ）２（ＩｍＨ０２」＾３＋的反应动力学。结果表明，反应遵循Ｈ．Ｔａｕｂｅ所提出的外配位界电子传递机理。在２５℃，Ｉ＝０．５ｍｏｌ．Ｌ＾－１，ｔｒａｎｓ－「Ｃｏ（ｅｎ）２（ＩｍＨ）２」＾３＋／「Ｆｅ（ＣＮ）６」＾４－反应体系的前驱配合物离子对形成常数为Ｑ１ｐ＝９８．９ｍｏｌ＾－１．Ｌ，电子转移速率常数为Ｋｍ＝１．     

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.     

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.     

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.     

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.