ZrCl4／AlEt2Cl和ZrCl4／AlEt2Cl—n—C4H9ONa催化剂体系锆的ESR动态表征

迄今为止关于锆的ESR研究报导甚少。CaMaTOB等发表了掺杂在YPO_4中的Zr~(3 )的ESR谱参数; Abraham等报导了俘获干磷酸单晶中Zr~(3 )的ESR研究;Kartel等用ESR手段表征了ZrPO_4的微孔结构;Robert等以LiAlH(OCMe_3)_3为还原剂由CP_2ZrCl(CH_2PPh_2)制得Cp_2ZrH(CH_2PPh_2),然后热解所得产物,观测到Zr~(3 )络合物的ESR信号;Atkinson等研究了有机金属锆系列化合物,获得有机自由基信号和Zr~(3 )的ESR信号。本文研究ZrCl_4的Ziegler-Natta体系催化乙烯齐聚中锆的价态及自旋浓度的变化。     

Nd(P204)3/AlEt3/第三组分体系催化乙炔聚合动力学

本文研究了乙炔在Nd(P)_3-AlEt_3-Ⅲ组分体系中的聚合动力学。结果表明聚合速率R_p与乙炔压力和催化剂浓度分别呈一级关系,即R_p=k＇[cat][P];发现聚合速率随时间按二级定律衰减,即dR~(-1)dt=k;提出活性中心以双分子失活的假设解释了实验结果。     

Enantioselective addition of AlEt3 to aldehydes catalyzed by titanium(IV)–TADDOLate complex

Enantioselective addition of AlEt₃ to aldehydes catalyzed by a titanium(IV)–TADDOLate complex was carried out with ee values up to 99% for 2-chlorobenzaldehyde as a substrate. The key success of the study resides in the choice of THF as a solvent. THF is capable of coordinating to Al(III) and is speculated to lower the Lewis acidity of AlEt₃ and thus to suppress the competing reaction from AlEt₃ itself.     

AlEt3-promoted eliminative ring-opening of β-hydroxy epoxides: highly stereoselective synthesis of terminal α-hydroxy olefins

AlEt₃-promoted eliminative ring-opening of β-epoxy alcohols leading to α-hydroxy olefins is reported. This eliminative ring-opening reaction is shown to be highly stereoselective, thus providing an alternative asymmetric synthesis for α-hydroxy olefins.     

Photosynthesis and Molecular Structure of2—Amino—3H—phenoxazin—3—one

1 INTRODUCTION 2-Amino-3H-phenoxazin-3-one (APX) is related to the naturally occurring antineoplastic actinomycin D and has been used as a chemical model of actinomycin D[1]. Usually APX is synthesized from 2-aminophenol with the phenoxazinone synthase in human body[2]. A variety of artificial synthesis methods of APX via the oxidation of 2-aminophenol have also been reported, but each method needs some artificial condition such as chemical catalysis[3～7], natural enzyme[8], UV…     

气相法LLDPE催化剂(MgCl2/TiCl4.THF/AlEt3)结构的红外光谱研究

近年来线型低密度聚乙烯(LLDPE)发展十分迅速.制造方法有气相法、溶液法等,气相法中以美国Union Carbide公司的Unipol技术最为重要.该公司早期的LLDPE专利采用铬系催化剂,近年来转向以四氢呋喃(THF)等给电子体改性的钛镁催化剂.与未改性的钛镁催化剂相比,其催化活性高,使乙烯与α-烯烃共聚的能力强,并易于调节分子量.显然,THF对改进催化剂的性能起了重要作用.关于MgCl_2/     

Anodic Dissolution of Aluminum in Liquid Electrolytes MF· 2AlEt3 (M = Na,K, Rb)

The kinetics of anodic dissolution of aluminum films electrodeposited on platinum via direct aluminum electrooxidation without preliminary discharge of electrolyte components is studied. The process probably involves adatoms and clusters Al* on the electrode surfaces, with limiting stage Al* – e (A1⁺)_ads.     

3—（3‘—羟基丁基）异苯并呋喃—1（3H）—酮的合成

由邻苯二甲酸酐为原料，经中间体３－羟基苯酞（３），再经溴丙烯及锡存在下３的烯丙基化、硼氢化氧化、铬酐氧化，二甲基锌甲基化，共６步反应合成了３－（３‘－羟基丁基）异苯并呋喃－１（３Ｈ）－酮。     

1—芳基—2—苯基—3—甲基—3—异丙基—2—氧代—1,4,2—二氮磷杂？…

利用取代苯基脲与苯基二氮化膦和３－甲基－２－丁酮进行的类Ｍａｎｎｉｃｈ反应合成了１５种新的１,４,２－二氮磷杂环戊－５－酮类化合物（２ａ－２ｏ）,其结构经＾１Ｈ ＮＭＲ,ＩＲ,ＭＳ和元素分析证实,根据ＮＭＲ谱分析,反应主要生成顺式几何异构体,除草活性测试表明,目标化合物对阔叶杂草具有很好的选择性草活性,并对其结构与除草活性关系进行了讨论。