稀土—谷氨酸配合物的pH电位法研究

报道了在生理条件下用ｐＨ电位法对１５种稀元素与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。     

稀土气态配合物PrAl3Cl12的热力学研究

用 对氯化镨与氯化铝形成气态配合物的反应（ＰｒＣｌ３（ｓ）＋（ｘ／２）Ａｌ２Ｃｌ６（ｇ）＝ＰｒＡｌｘＣｌ３ｘ＋３），进行了研究，实验显示，在６０４－８８２７Ｋ、０．０５－０．１５ＭＰａ条件下，ＰｒＡｌ３Ｃｌ１２配合物是唯一产物。测定了配合物的稳定常数，计算了反应的焓变和熵变，并讨论了其误差。     

稀土、钙的DL苹果酸和L羟脯氨酸混配配合物研究

在模拟生理条件（３７℃，０．１５ｍｏｌ．Ｌ＾－１ＮａＣｌ）用ＰＨ电位法测定了１４种稀土、钙的ＤＬ－苹果酸和Ｌ－羧脯氨酸二元、三元配合的稳定常数，用计算机优化确定了 二元体纱，苹果酸配合物存在１１０１、１１００和１２００型，     

稀土,钙的DL—苹果酸和L—羟脯氨酸混配配合物研究

在模拟生理条件（３７℃，０．１５ｍｏｌ．Ｌ＾－１ＮａＣｌ）用ＰＨ电位法测定了１４种稀土、钙的ＤＬ－苹果酸和Ｌ－羧脯氨酸二元、三元配合的稳定常数，用计算机优化确定了 二元体纱，苹果酸配合物存在１１０１、１１００和１２００型，     

外消旋丙一丝二肽及其稀土配合物的NMR性质

研究了不同ｐＨ值下的Ｄ，Ｌ－丙氨酰－Ｄ，Ｌ－丝氨酸（Ａｌａ－Ｓｅｒ）及其稀土配合物的１Ｈ、１３ＣＮＭＲ谱，对于该种二肽的不同旋光异构体，有可能对其谱线进行区分和指认。测定了酸解常数和稀土配合物的络合稳定常数。通过分离Ａｌａ－Ｓｅｒ的重稀土配合物的接触位移和偶极位移。分析了不同异构体配合物的ＮＭＲ位移的原因。     

外消旋丙—丝二肽及其稀土配合物的NMR性质

不同ｐＨ值下的Ｄ，Ｌ－丙氨酰－Ｄ，Ｌ－丝氨酸及其稀土配合物的＾１Ｈ，＾１３ＣＮＭＲ谱，对于该种二肽的不同旋光异构体，有可能对其谱线进行区分和指认。测定了酸解常数和稀土配合物的络合稳定常数。通过分离Ａｌａ－Ｓｅｒ的重稀土配合物的接触位移和偶极位移。分析了不同异构体配合物的ＮＭＲ位移的原因。     

M（Ⅱ）（ArP）~（2－）与核酸碱基（腺嘌呤，胞嘧啶）三元混配配合物稳定性研究

用ｐＨ电位滴定法测定了金属离子（Ｍ~（２＋）＝Ｃｕ~（２＋），Ｃｏ~（２＋），Ｎｉ~（２＋），Ｚｎ~（２＋），Ｃｄ~（２＋）与核酸碱基（Ｌ＝腺嘌呤，胞嘧啶）形成的二元配合物以及与腺昔－５’－三磷酸（ＡＴＰ）形成的三元混配配合物的稳定常数。三元配合物相对于二元配合物的稳定性用平衡常数表示。结果表明：ΔｌｇＫ_ｍ比咪唑或氨的相应配合物ΔｌｇＫ_ｍ大，这可能与三元混配配合物分子内存在配体间的芳环堆积、氢键作用以及π_Ａ－π_Ｂ协同效应有关。     

平衡移动法测定M_mR_n型配合物组成和稳定常数的研究

根据平衡移动原理推导出一种能判别单核或多核配合物并直接测定ＭｍＲｎ型配合物组成和稳定常数的平衡移动法公式ｌｇ（Ａｉ／（Ａｍａｘ－Ａｉ）ｍ）＝ｎｌｇｃ′Ｒ＋ｌｇ（ｍ·β·ˉ（ｃＭ／Ａｍａｘ）（ｍ－１）。用Ｓｃ３＋－ＣＰＡⅢ和Ｆｅ３＋ＣＡＳ两个配合反应体系加以验证，结果令人满意。     

钾（Ⅰ）（4＇－溴苯并－15－冠－5）配合物的研究

合成了两种新型的固体配合物，其组成为Ｋ（ＢｒＢ１５Ｃ５）Ｘ（Ｘ＝ＮＣＳ￣－或Ｐｉｃ￣－）．钾（Ⅰ）离子不仅能与４’－溴苯并－１５－冠－５形成常见的１：２夹心式配合物，而且还能生成稳定的１：１型（Ｍ：Ｌ）固体配合物．     

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下（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。     

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%.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

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.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

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.