Catalyst shuttling enabled by a thermoresponsive polymeric ligand: facilitating efficient cross-couplings with continuously recyclable ppm levels of palladium
作者:Erfei Wang、Mao Chen
DOI:10.1039/c9sc02171j
日期:——
A polymeric monophosphine ligand WePhos has been synthesized and complexed with palladium(II) acetate [Pd(OAc)2] to generate a thermoresponsive pre-catalyst that can shuttle between water and organic phases, with the change being regulated by temperature. The structure of the polymeric ligand was confirmed with matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) mass spectrometry
[EN] 2,6-DISUBSTITUTED PYRIDINES AS SOLUBLE GUANYLATE CYCLASE ACTIVATORS<br/>[FR] PYRIDINES 2,6-DISUBSTITUÉES COMME ACTIVATEURS DE LA GUANYLATE CYCLASE SOLUBLE
申请人:SMITHKLINE BEECHAM CORP
公开号:WO2009071504A1
公开(公告)日:2009-06-11
Disclosed are compounds of formula (I) wherein R1 and R2 are independently selected from hydrogen, halo, CF3, C1-4alkyl and allyl; Y represents (II), (III), (IV) or (V) wherein R3 represents CF3 or C1-4alkyl; and R3a represents CF3 or C1-4alkyl.
PdO hydrate as an efficient and recyclable catalyst for the Suzuki–Miyaura reaction in water/ethanol at room temperature
作者:Francesco Amoroso、Sara Colussi、Alessandro Del Zotto、Jordi Llorca、Alessandro Trovarelli
DOI:10.1016/j.catcom.2010.11.026
日期:2011.2
efficient catalysts for the Suzuki–Miyaura reaction in ethanol/water mixture at roomtemperature in air. Thus, in the presence of 1 mol% catalyst, the reaction between different aryl bromides and arylboronic acids afforded a wide range of functionalized biphenyls in quantitative yield. Catalyst 1 has shown to be the most active for all couples of substrates, and it can be recovered and recycled several
我们的实验室中制备的PdO·1.4H 2 O 1以及市售的氧化钯2–4可在室温下在空气中在乙醇/水混合物中作为Suzuki–Miyaura反应的有效催化剂。因此,在1mol%催化剂的存在下,不同的芳基溴化物和芳基硼酸之间的反应以定量收率提供了广泛的官能化联苯。催化剂1已证明对所有底物夫妇都具有最强的活性,可以将其回收和再循环多次,而活性没有明显降低。通过适当的测试已经证明,真正的催化剂是可溶形式的钯,其是通过从金属氧化物前体中浸出金属而产生的。值得注意的是,溶液中和分离出的有机产物中催化剂的量均为约1 ppm。
Synthesis of Substituted Biarylmethanol via Ferrocenyloxime Palladacycles Catalyzed Suzuki Reaction of Chlorophenylmethanol in Water
作者:Hong-Mei Li、Ai-Qing Feng、Xin-Hua Lou
DOI:10.5012/bkcs.2014.35.8.2551
日期:2014.8.20
4-(hydroxymethyl)phenylboronic acid for the synthesis of substituted biarylmethanols in water. However, substrates are limited to the aryl bromides and activated aryl chlorides. To date, there is no report that investigates the Suzuki reaction of chlorophenylmethanol in water. As a continuation of our interest in the synthesis of biarylmethanols, we have prepared a newphosphine adduct of palladacycle 2 from the
Molecular Flexibility and Bend in Semi‐Rigid Liquid Crystals: Implications for the Heliconical Nematic Ground State
作者:Richard J. Mandle、John W. Goodby
DOI:10.1002/chem.201903677
日期:2019.11.13
consisting of two rigid mesogenic units linked by a flexible oligomethylene spacer of odd parity, giving a bent shape. We report the synthesis and characterisation of two novel dimeric liquidcrystals, and perform a computational study on 10 cyanobiphenyl dimers with varying linking groups, generating a large library of conformers for each compound; this allows us to present molecularbend angles as probability
NTB相具有螺距长度为几纳米的局部螺旋结构,并且通常由由两个刚性介晶单元组成的材料显示,所述刚性介晶单元通过奇数奇偶性的柔性低聚亚甲基间隔基连接,形成弯曲的形状。我们报告了两种新型二聚液晶的合成和表征,并对10个具有不同连接基团的氰基联苯二聚体进行了计算研究,为每个化合物生成了一个庞大的构象库。这使我们能够将分子弯曲角表示为许多构象异构体的概率加权平均值,而不是使用单个构象异构体。我们通过比较质子间距离与从基于溶液的1D 1 H NOESY NMR获得的质子间距离,来验证构象库,发现实验与计算工作之间有很好的一致性。反过来,我们发现,使用任何单个构象异构体均无法重现实验质子间的距离。我们发现使用单个构象异构体会大大高估分子弯曲角,同时也忽略了灵活性。此外,我们表明平均弯曲角和柔韧性都与NTB相的相对稳定性有关。