Cp*rhodium and iridium complexes with bisoxazolines: synthesis, fluxionality and applications as asymmetric catalysts for Diels–Alder reactions
作者:David L Davies、John Fawcett、Shaun A Garratt、David R Russell
DOI:10.1016/s0022-328x(02)01859-4
日期:2002.11
Reaction of the dimers [MCl2CP*](2) (M = Rh, It) with bis-oxazolines [N-N = bis(2-oxazoline) (box), 2,2-bis(2-oxazolinyl)propane (bop), 1,2-bis(2-oxazolinyl)benzene (benbox)] in the presence of NaSbF6 (or KPF6) gives complexes [MCl(N-N)Cp*] [EF6] (E = P or Sb) which have been fully characterised. Treatment of some of these with AgSbF6 generates dications [Rh(OH2)(N-N)Cp*]2(+), some of which are fluxional at room temperature. One of these is an enantioselective catalyst for the Diels-Alder reaction of methacrolein and cyclopentadiene. Three complexes, [RhCl(Pr-i-box)Cp*][SbF6], [RhCl(Pr-i-bop)Cp*][SbF6] and [RhCl(Et-benbox)Cp*][SbF6] have been characterised by X-ray crystallography. (C) 2002 Elsevier Science B.V. All rights reserved.
Surfactant-Assisted Nanocrystalline Zinc Coordination Polymers: Controlled Particle Sizes and Synergistic Effects in Catalysis
作者:Chao Huang、Huarui Wang、Xiaolu Wang、Kuan Gao、Jie Wu、Hongwei Hou、Yaoting Fan
DOI:10.1002/chem.201505009
日期:2016.4.25
Different morphologies and particle sizes of two crystalline zinc‐based coordination polymers (CPs), [Zn(pytz)H2O]n (1; H2pytz=2,6‐bis(tetrazole)pyridine) and [Zn2(pytz)24 H2O] (2), from the bulk scale to the nanoscale, could be obtained under solvothermal conditions with different surfactants (polyvinylpyrrolidone (PVP) or polyethylene glycol (PEG) 2000) as templates. PVP and PEG 2000 could act as
[Zn(pytz)H 2 O] n(1 ; H 2 pytz = 2,6-双(四唑)吡啶)和[Zn 2(pytz) )2 4 H 2 O](2),可以从体积尺度到纳米尺度,在溶剂热条件下,以不同的表面活性剂(聚乙烯吡咯烷酮(PVP)或聚乙二醇(PEG)2000)为模板获得。PVP和PEG 2000分别可以用作封端剂和结构导向剂,以影响晶体颗粒的生长并控制其尺寸。CP 1展示了一个带有窗口状单元和2的二维框架显示了双金属结构。纳米晶体1和2被用作非均相催化剂,以研究相邻的催化活性位点如何在芳族二腈直接催化转化为恶唑啉的过程中协同影响其催化活性。结果表明,在相同的反应条件下,有1个以双恶唑啉为唯一产物,而有2个以单恶唑啉为主要产物。