采用Seemann—Bohlin准聚焦X射线衍射仪测量薄膜厚度的误差理论分析

本文从理论上分析了衍射强度比偏差Δ（Ｉ／Ｉ∞）和衍射峰位偏差△２θ对Ｓｅｅｍａｎｎ－Ｂｏｈｌｉｎ准聚焦Ｘ射线衍射仪测量表面单层薄膜厚度误差的影响。分析结果表明，降低Δ（Ｉ／Ｉ∞）可提高膜厚的测量精度，在Δ（Ｉ／Ｉ∞）一定的情况下，按μρｔ［Ｓｉｎ＾－１γ＋Ｓｉｎ＾－１（２θ－γ）］＝１选择靶辐射和衍射晶面可使由Δ（Ｉ／Ｉ∞）导致的膜厚测量误差具有极小值；选择高角度衍射线有助于减小试样离焦引起的衍射     

二苯并18－冠－6铵与硫氰酸银配合物的晶体结构

标题化合物［（ＮＨ_４）（ＤＢ１８Ｃ６）］_２［Ａｇ（ＳＣＮ）_２］_２其晶体属三斜晶系，空间群为Ｐ１。晶胞参数：ａ＝１４．００３（２），ｂ＝１４．４６１（３），ｃ＝１４．８８７（２），ａ＝６６．５１（２），β＝６６．７０（１），γ＝７６．０９（２）°，Ｖ＝２５２７．１３　３，Ｍ_ｒ＝１２０５．０，Ｚ＝２，Ｄ_ｘ＝１．５８ｇ／ｃｍ~３，μ＝９．８８ｃｍ~（－１）。偏差因子Ｒ_ｗ＝０．０８１，独立可观测点数［Ｉ＞３σ（Ｉ）］为３３５１个，在配合物分子中，二苯并１８－冠－６与ＮＨ４~＋形成配阳离子，Ａｇ~＋与硫氰酸根形成配阴离子，二者以静电力形成配合物。银原子被两个ＳＣＮ~－的Ｓ原子桥联和硫氰酸根上的硫，氮杂配，使整个分子形成一条高分子长链。     

二苯并18－冠－6铵与硫氰酸银配合物的晶体结构

标题化合物［（ＮＨ_４）（ＤＢ１８Ｃ６）］_２［Ａｇ（ＳＣＮ）_２］_２其晶体属三斜晶系，空间群为Ｐ１。晶胞参数：ａ＝１４．００３（２），ｂ＝１４．４６１（３），ｃ＝１４．８８７（２），ａ＝６６．５１（２），β＝６６．７０（１），γ＝７６．０９（２）°，Ｖ＝２５２７．１３　３，Ｍ_ｒ＝１２０５．０，Ｚ＝２，Ｄ_ｘ＝１．５８ｇ／ｃｍ~３，μ＝９．８８ｃｍ~（－１）。偏差因子Ｒ_ｗ＝０．０８１，独立可观测点数［Ｉ＞３σ（Ｉ）］为３３５１个，在配合物分子中，二苯并１８－冠－６与ＮＨ４~＋形成配阳离子，Ａｇ~＋与硫氰酸根形成配阴离子，二者以静电力形成配合物。银原子被两个ＳＣＮ~－的Ｓ原子桥联和硫氰酸根上的硫，氮杂配，使整个分子形成一条高分子长链。     

簇合物〔WOS_3Cu_3(V-pic)_6〕Br 的合成和晶体结构

簇合物〔ＷＯＳ３Ｃｕ３（γ－ｐｉｃ）６〕Ｂｒ（Ｃ３６Ｈ４２ＢｒＯＮ６Ｓ３Ｃｕ３Ｗ, Ｍｒ＝ １１２５．３４） 属于三方晶系,空间群为Ｐ３,晶胞参数为：ａ＝ １２．２６４（５）, ｃ＝ １５．９０５（８） , γ＝ １２０．００°, Ｖ＝２０７１（２）３, μ（ＭｏＫα）＝ ５．４９０ｍ ｍ － １, Ｚ＝ ２, Ｄｃ＝ １．８０４ｇ／ｃｍ ３, Ｆ（０００）＝ １１０４ , Ｒ＝ ０．０５２ , ｗ Ｒ＝ ０．０５３． 可观察衍射点１９０１ （Ｉ≥２σ（Ｉ））。该簇合物的分子由游离的阴离子Ｂｒ－ 和簇阳离子〔ＷＯＳ３Ｃｕ３（γ－ｐｉｃ）６〕＋ 构成。阳离子中的Ｗ 原子、Ｓ原子和Ｃｕ原子构成１ 个巢状骨架结构,且该结构中存在一个通过Ｗ 和Ｏ原子的Ｃ３ 轴。     

[Fe(CN)_6]~(4-)还原trans-[Co(en)_2(ImH_)2]~(3+)的电子转移反应动力学机理

在不同的温度下，考察了六氰合铁（Ⅱ）配阴离子［Ｆｅ（ＣＮ）６］４－还原ｔｒａｎｓ－［Ｃｏ（ｅｎ）２（ＩｍＨ）２］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，电子转换速率常数为Ｋｅｔ＝１．３×１０－４ｓ－１，电子转移过程活化焓ΔＨ≠ｅｔ和活化熵ΔＳ≠ｅｔ分别为１４１．２ｋＪ·ｍｏｌ－１、５７３．５Ｊ·ｍｏｌ－１·Ｋ－１。     

（四甲基二硅撑）双（3－三甲硅基环戊二烯基）－四羰基二铁的反应性

标题化合物（Ｍｅ_２ＳｉＳｉＭｅ_２）［η￣５－（３－Ｍｅ_３ＳｉＣ_５Ｈ_３）Ｆｅ（ＣＯ）_２］_２／（μ－ＣＯ）_２（Ａ）分子中的Ｆｅ－Ｆｅ键被钠汞齐还原断裂，生成相应的双铁负离子，分别与ＭｅＣＯＣｌ、ＰｈＣＯＣｌ、ＰｈＣＨ_２Ｃｌ、ＣｌＣＨ_２ＣＯＯＣ_２Ｈ_５和Ｐｈ_３ＳｎＣｌ进行亲核取代反应，生成在铁原子上引入相应取代基的产物（Ｍｅ_２ＳｉＳｉＭｅ_２）［η￣５－（３－Ｍｅ_３ＳｉＣ_５Ｈ_３）Ｆｅ（ＣＯ）_２Ｒ］_２（Ｒ：ＭｅＣＯ（１），ＰｈＣＯ（２），ＰｈＣＨ_２（３），ＣＨ_２ＣＯＯＣ_２Ｈ_５（４），Ｐｈ_３Ｓｎ（５），Ｉ（６））。Ａ在氯仿中与碘反应，得到Ｆｅ－Ｆｅ断裂的双铁碘化物，但在苯中与过量碘反应，则得到Ｆｅ－Ｉ－Ｆｅ桥联的离子型化合物（Ｍｅ_２ＳｉＳｉＭｅ_２）［η￣５－（３－Ｍｅ_３ＳｉＣ_５Ｈ_３）Ｆｅ（ＣＯ）_２］_２Ｉ·Ｉ（７）。化合物６的晶体和分子结构经Ｘ射线衍射测定，６属单斜晶系，Ｐ２１／ｃ空间群，ａ＝１．７２１７（４）ｎｍ，ｂ＝０．７７５３（２）ｎｍ，Ｃ＝１．３６２９（７）ｎｍ，β＝１０３．８０（３）°，Ｖ＝１．７６７（２）ｎｍ３，Ｚ＝４，Ｄｃ＝１．６２９９·ｃｍ－１，最终偏差因子Ｒ＝０．０５４。     

Schiff碱N-氧化吡啶-2-甲醛缩氨基硫脲的晶体结构

合成了标题Ｓｃｈｉｆｆ碱并获得了其单晶,化学式为Ｃ７Ｈ８Ｎ４ＯＳ,Ｍｒ＝ １９６．２３,经Ｘ射线单晶衍射分析,该晶体属于单斜晶系,空间群为Ｃ２／ｃ,晶胞参数： ａ＝ １３．１９８（２）,ｂ＝ ８．０７０（１）,ｃ＝ １６．９９９（２）,β＝ １０２．７６０（１０）°,Ｖ＝ １７６５．８（４）３,Ｚ＝ ８,Ｄｃ＝１．４７６ｇ／ｃｍ ３,μ＝ ０．３３０ｍ ｍ － １,Ｆ（０００）＝ ８１６,在２．４６°＜ θ＜ ２９．００°范围内以ω扫描方式收得独立衍射点２３４７ 个,其中Ｉ＞ ２σ（Ｉ）的可观测点为１６８７ 个。最终偏离因子Ｒ＝０．０３４４,ｗ Ｒ＝ ０．０８４３,（Δ／σ）ｍ ａｘ＝ ０．００１,Ｓ＝ １．０８２。分子为平面构型。与相应配合物的晶体结构进行了比较并讨论了配位前后标题化合物主要的键性质的变化。     

三核钼－硫簇合物的低热固相合成及其晶体结构

三核钼－硫配合物Ｍｏ_３Ｓ_７（ｄｔｃ）_３Ｉ·Ｓ_８·２ＣＨ_２Ｃｌ_２（ｄｔｃ＝Ｃ_４Ｈ_８ＮＣＳ_２~－）是由低热固相合成得到的。晶体属单斜晶系，Ｍ_ｒ＝１５００．１９，空间群Ｐ２_１／ｎ，ａ＝１１．８８１（３），ｂ＝１５．５５９（４），ｃ＝２６．１９７（７），β＝９８．５３（２）°，Ｖ＝４７８９Ａ~３，Ｚ＝４，Ｄ_ｃ＝２．０８ｇ／ｃｍ~３，Ｆ（０００）＝２９２０，μ（ＭｏＫα）＝２５．２４ｃｍ~（－１），对于２３９７个Ｉ≥３σ（Ｉ）的独立衍射点，最终偏离因子Ｒ＝０．０６０，Ｒ＝０．０６６。该配合物的基本骨架是［Ｍｏ_３Ｓ_７（ｄｔｃ）_３］~＋，其簇芯为［Ｍｏ_３Ｓ_７］~（４＋）单元，３中Ｍｏ原子组成正三角形平面，Ｍｏ－Ｍｏ的平均键长力２．７２３，Ｍｏ原子平面上的硫原子形成盖帽的μ_３－Ｓ，其Ｍｏ－Ｓ平均键长为２．３８３Ａ，３个Ｓ_２基团分别位于三角形３个棱的外侧，并分别与邻近的两个Ｍｏ原子结合形成１２中Ｍｏ－Ｓ键。与μ_３－Ｓ相对而位于平面另一侧的Ⅰ原子与３个μ_２－Ｓ连结，平均距离为３．２５７Ａ，成键作用较弱。     

MTIR对铑的吸附及铑与贱金属分离的研究

采用Ｎ－甲基－２－硫咪唑树脂（Ｎ－ｍｅｔｈｙｌ－２－ｔｈｉｏ－ｉｍｉｄａｚｏｌｅｒｅｓｉｎ，简称ＭＴＩＲ）对Ｒｈ（Ⅲ）进行吸附性试验．确定树脂吸附的最佳条件，测得Ｒｈ（Ⅲ）的吸附速率ｔ１／２＝８４ｍｉｎ，吸附客量１．３７ｍｍｏｌＲｈ（Ⅲ）／ｇＭＴＩＲ（１４０．５ｍｇＲｈ（Ⅲ）／ｇＭＴＩＲ）．吸附摩尔配位比０．３４［Ｒｈ（Ⅲ）／功能基］，分配系数Ｄ＝２．０５×１０３ｍｌ·ｇ－１．并对Ｒｈ（Ⅲ）与Ｆｅ３＋、Ｃｏ２＋、Ｎｉ２＋、Ｃｕ２＋混合离子进行选择性吸附研究，使Ｒｈ（Ⅲ）与其他贱金属离子分离．对ＭＴＩＲ树脂柱上的Ｒｈ（Ⅲ）进行二次洗脱，在２％硫脲的丙酮溶液与等体积的６ｍｏｌＨＣｌｄｍ－３的盐酸的混合溶液条件下可达定量回收．     

固相配位化学反应研究：LXVII.金属铜表面M—S（M=Mo,W）簇合物的组成

采用ＦＴＩＲ、ＸＰＳ和ＡＥＳ研究了金属铜表面Ｍ－Ｓ（Ｍ＝Ｍｏ，Ｗ）簇合物膜。结果表明，Ｍｏ（Ｗ）Ｓ＾２－４与铜表面的Ｃｕ２Ｏ反应，形成了Ｍｏ（Ｗ）－Ｓ－Ｃｕ键。簇合物膜由Ｍｏ（Ｗ），Ｓ，Ｃｕ，Ｏ元素组成，分别呈＋６、－２、＋１、－２价，膜为多分子层结构并保持，ＭｏＳ４或ＷＳ２单元，膜表面只有Ｃｕ，Ｏ而不存在Ｍｏ（Ｗ），Ｓ，膜层厚度与反应时间有关，时间越长，膜越厚，膜为多组分的复杂体系，其颜色是各组     

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.     

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.     

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.     

Microwave-assisted copper-catalyzed stereoselective ring expansion of three-membered heterocycles with α-diazo-β-dicarbonyl compounds

Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular S_N2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.     

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%).