Transfer Hydrogenation of C= C Double Bonds Catalyzed by Ruthenium Amido-Complexes: Scopes, Limitation and Enantioselectivity

The reduction of C = C double bonds is one of the most fundamental synthetic transformations and plays a key role in the manufacturing of a wide variety of bulk and fine chemicals. Hydrogenation of olefinic substrates can be achieved readily with molecular hydrogen in many cases, but transfer hydrogenation methods using suitable donor molecules such as formic acid or alcohols are receiving increasing attention as possible synthetic alternatives because it requires no special equipment and avoids the handling of potentially hazardous gaseous hydrogen.     

Preparation of Ce-Zr-O solid solution

A single phase solid solution of Ce-Zr-O can be made by using NH₄HCO₃ solution as precipitating agent. The influence of preparation conditions, such as pH, Zr⁴⁺/(CO₃ ^2-+HCO₃ ^-) and Ce³⁺/Zr⁴⁺ ratio on the formation of the solid solution were investigated. The results show that a single phase Ce-Zr-O solid solution can be formed only under a narrow window of preparation conditions, indicating that some compounds are formed in the precipitating process. The compound may contain Ce³⁺, Zr⁴⁺, CO₃ ^2-, HCO^3-, and OH^-. The solid solution so prepared can be described as Ce_0.37Zr_0.63O₂. This revised version was published online in August 2006 with corrections to the Cover Date.     

大环二萜天然产物(±)-Mayol的全合成

西松烷型二萜类化合物是一大类广泛分布于松脂、烟草、陆地动物及海洋生物体中的具有十四元碳环骨架的化合物.其结构新颖复杂,且大多具有显著和广谱的生物活性.近几十年来,有关这类化合物的研究已引起了人们的极大兴趣.因此,开展这类天然产物及其类似物的全合成及构效关系的研究不仅具有重要的学术价值,而且具有潜在的应用前景.     

Synthesis and Crystal Structure of 1,4-Bis(2-hydroxymethylphenyl)-1,4-dioxabutane

1 INTRODUCTION Macrocyclic ligands and their metal complexes have received much attention due to their applications in ion transport, ion separation and as models in biomimic researches[1~7]. The synthetic methods of macrocyclic ligands and their metal complexes are mainly divided into three kinds[8]. The first one is synthesizing free ligand, then forming the metal complexes; the second is template synthesis; and the third is synthesizing the end-off or side-off precursor ligand, then c…     

~1Σ~＋Ni─CO分子簇的从头算研究

采用ＵＨＦ及ＵＭＰ＿２方法，对~１Σ~＋Ｎｉ─ＣＯ分子簇的成键机制进行了从头算研究。计算表明，在σ空间，Ｎｉ~１Ｓ（ｄ~（１０））导出态的主要成键特征是ＣＯ５σ→Ｎｉ４ｓ的授键作用；而Ｎｉ~１Ｄ（ｄ~９ｓ~１）导出态的主要特征是４ｓｐ＿σ极化。在~１Σ~＋Ｎｉ─ＣＯ分子簇中总的成键机制是：ｄ~（１０）导出态中π反馈作用大于σ授键作用；而ｄ~９ｓ~１导出态中σ授键作用强于π反馈作用。由于接受配键机制一定伴随着轨道之间的重叠，因而为了给出合理的Ｍ─Ｌ作用分析，进行补偿计算是重要的。     

微铂电极上1-酰基二茂铁动力学参数的测定

本文合成并研究了１－酰基二茂铁在ＣＨ２Ｃｌ２中的伏安行为，测定了它们在ＣＨ２Ｃｌ２中不同支持电解质浓度时的扩散系数，并分明用Ｚ．Ｇａｌｕｓ和Ｋ．Ａｏｋｉ方法计算了两种状态下的电子迁移速率常数。讨论了取代基的诱导效应和共轭效应及其链长对１－酰基二茂铁的动力学性质的影响以及支持电解质及其浓度等因素对伏安曲线的影响。     

一维链配位聚合物[Mn(acacen){N(CN)2}]n的合成、结构和性质的研究(英)

The manganese(Ⅲ) complex [Mn(acacen){N(CN)₂}]_n [H₂acacen=bis(acetylacetone)ethylenediimine] has been synthesized and the structure has been determined. The complex forms a one-dimensional chain structure via the bidentate bridge ligand μ_1,5-[N(CN)₂]^- linking [Mn(acacen)] moiety. The magnetic property of the compound (75～300 K) shows the existence of an antiferromagnetic exchange interaction among paramagnetic centers along the chain. CCDC: 244940.     

离子液体中用Heck反应合成2-取代萘烯丙醇化合物

利用Heck反应, 在离子液体、金属钯或镍、碱和膦配体反应体系中, 由卤代萘与烯丙醇反应, 制得了高收率和高选择性的2-取代萘烯丙醇化合物. 该方法原料便宜易得、操作简单、反应体系可循环使用. 并讨论了醋酸镍替代醋酸钯、不同膦配体、溶剂及碱对反应转化率的影响. 通过核磁共振、红外光谱、质谱和元素分析对产物的结构进行了表征.     

ICP-AES法测定炉渣中三氧化二铝含量

炉渣是钢铁冶炼和精炼过程中的重要产物之一,主要成分有CaO、FeO、MnO、MgO等碱性氧化物,SiO2、P2O5、Fe2O3等酸性氧化物和Al2O3两性氧化物,其中还有少量的硫化物.目前,炉渣的主要分析方法可采用化学法、原子吸收光谱法、X射线荧光光谱法和电感耦合等离子体原子发射光谱法等[1].但由于炉渣中基体成分较为复杂,需分析的元素较多,常规化学法通常采用EDTA容量法[2]、沉淀分离-EDTA容量法和CyDTA容量法等[3],它存在试样前处理相对烦琐,速度慢并且测试结果精密度不高的缺点;原子吸收光谱法测定高浓度的铝元素时,存在其它干扰元素不易去除的缺点;而X射线荧光光谱法在粉末压片时需取用较多的试样;本方法采用ICP-AES法,称样量仅为0.1 g,经湿法消解溶样后,定容于100 mL容量瓶中,即可上机测定,分析时间短,准确度和精密度高(所测结果参加了CNAL T0144炉渣中三氧化二铝检测能力验证比对实验,并顺利通过能力验证).     

新型氮芥和卤代烷基哌嗪芳香醛的合成

通过对Vilsmeier反应、烷基化反应和氯化反应的改进提出了以简单易得的苯胺和苯基哌嗪为原料制备氮芥和哌嗪芳香醛的方法. 采用该改进的方法合成了8个氮芥和哌嗪芳香醛, 其中7个为新化合物. 它们的结构均经质谱、红外光谱、核磁共振谱和元素分析确证.