Carboxylate-Bridged Diiron(II) Complexes: Synthesis, Characterization, and O<sub>2</sub>-Reactivity of Models for the Reduced Diiron Centers in Methane Monooxygenase and Ribonucleotide Reductase
作者:Susanna Herold、Stephen J. Lippard
DOI:10.1021/ja9628563
日期:1997.1.1
Diiron(II) complexes with an oxygen-rich coordination environment were assembled with the dinucleating dicarboxylate ligands m-xylylenediamine bis(Kemp's triacid)imide (H2XDK) and the more soluble analogue m-xylylenediamine bis(propyl Kemp's triacid)imide (H2PXDK). X-ray crystallographic analysis revealed that, in most of the complexes, only one monodentate N-donor ligand is bound to each iron(II)
具有富氧配位环境的二铁 (II) 配合物与双核二羧酸配体间苯二甲胺双(坎普三酸)亚胺(H2XDK)和更易溶解的类似物间苯二甲胺双(丙基坎普三酸)亚胺(H2PXDK)组装在一起。X 射线晶体学分析表明,在大多数配合物中,只有一个单齿 N 供体配体与每个铁 (II) 离子结合。除了 XDK 和 PXDK 之外,还有多种其他配体桥接双金属核,包括氯化物、氟化物、三氟甲磺酸盐或羧酸盐。三(羧酸盐桥接)配合物 [Fe2(μ-XDK)(μ-O2CPh)(ImH)2(O2CPh)(MeOH)] (3) 和 [Fe2(μ-O2CC(CH3)3)(μ-PXDK )(N-MeIm)2(O2CC(CH3)3)] (4) 与甲烷单加氧酶 (MMO) 的羟化酶成分和核糖核苷酸还原酶 (RNR) 的 R2 蛋白中的二铁 (II) 核心具有相同的配体组成)。3和4中两个铁中心的配位环境是不等价的,一个铁是6配位的,另一个是4配位的。桥
Cyclopropanation of styrenes and stilbenes using lithiomethyl trimethylammonium triflate as methylene donor
作者:Juan M. Sarria Toro、Tim den Hartog、Peter Chen
DOI:10.1039/c4cc04929b
日期:——
Soluble lithiomethyl trimethylammonium triflate can cyclopropanate styrenes and stilbenes efficiently. Kinetic experiments support a carbolithiation-ring closure mechanism.
Carboxylate Catalyzed Isomerization of β,γ‐Unsaturated
<i>N</i>
‐Acetylcysteamine Thioesters**
作者:Saara Riuttamäki、Gergely Laczkó、Ádám Madarász、Tamás Földes、Imre Pápai、Anton Bannykh、Petri M. Pihko
DOI:10.1002/chem.202201030
日期:2022.8.10
The power of carboxylates: Simple carboxylate salts can rival strong amidine bases, such as DBU, in their catalytic power to isomerize β,γ-unsaturated thioesters to corresponding conjugated α,β-unsaturated thioesters. The mechanism involves a rate-determining protonation step!
COMPOSITION FOR POROUS FILM FORMATION, POROUS FILM, PROCESS FOR PRODUCING THE SAME, INTERLAYER INSULATION FILM AND SEMICONDUCTOR DEVICE
申请人:MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
公开号:EP1568744A1
公开(公告)日:2005-08-31
A composition for film formation from which a porous film excelling in dielectric characteristics, adherence, coating film uniformity and mechanical strength and realizing reduced moisture absorption can be prepared; a porous film and a process for producing the same; and a highly reliable semiconductor device of high performance wherein the porous film is incorporated. In particular, a composition for porous film formation, obtained by adding to a siloxane polymer at least one quaternary ammonium salt represented by the general formula: [(R<1>)4N]<+>[R<2>X]<-> (1), or Hk[(R<1>)4N]m<+>Y (2) wherein X represents CO2, OSO3 or SO3; Y represents SO4, SO3, CO3, O2C-CO2, NO3 or NO2; k is 0 or 1; each of m and n is 1 or 2; when n=1, k=0 and m=1; and when n=2, either k=0 and m=2, or k=1 and m=1.
New trimerization catalysts from sterically hindered salts
申请人:Air Products and Chemicals, Inc.
公开号:EP1852448A2
公开(公告)日:2007-11-07
The present invention provides trimerization catalyst compositions having a sterically hindered carboxylate salt and methods to produce a polyisocyanurate/polyurethane foam using such trimerization catalyst compositions.