β-hydroxyphosphonate analogues is described. The use of a nucleoside β-ketophosphonate as the key intermediate allowed both the (R) and (S) isomers of β-hydroxyphosphonate analogues in the pyrimidineseries to be accessed. Such derivatives may be considered as stable mimics of 5
描述了获得核苷 β-羟基膦酸酯类似物的简明途径。使用核苷 β-酮膦酸酯作为关键中间体允许获得嘧啶系列中 β-羟基膦酸酯类似物的 (R) 和 (S) 异构体。这样的衍生物可以被认为是 5
An Industrial Perspective on Counter Anions in Gold Catalysis: On Alternative Counter Anions
作者:Jasmin Schießl、Jürgen Schulmeister、Angelino Doppiu、Eileen Wörner、Matthias Rudolph、Ralf Karch、A. Stephen K. Hashmi
DOI:10.1002/adsc.201800629
日期:2018.10.18
counter anions was investigated by means of a variety of well‐known test reactions representing the key reactivity patterns of homogeneous gold catalysis, the catalytic activity was monitored by GC and 1H NMR. As previously reported, the counter anion influence is usually more pronounced than the corresponding ligand effect. Due to this, the study is focused on the investigation of counter anions so far
通过多种代表均相金催化关键反应模式的众所周知的测试反应,研究了多用途抗衡阴离子的比较,并通过GC和1 H NMR监测了催化活性。如前所述,抗衡阴离子的影响通常比相应的配体效应更为明显。因此,本研究的重点是迄今为止对均金催化反应的研究中还没有包括的抗衡阴离子的研究。使用到目前为止被忽略的抗衡阴离子(BAr F 4)-,[B(C 6 F 5)4 ] -,[Al(OC(CF 3)3)4 ] -和[B(C 6 F 5)3(OAc F)] -表现出超过或至少与常用抗衡阴离子相似的催化活性。抗衡阴离子的广泛使用在将来有关金催化中的催化剂优化方面可发挥重要作用。
Cyclopropenylylidene-Stabilized Diaryl and Dialkyl Phosphenium Cations: Applications in Homogeneous Gold Catalysis
Cationic but electron‐rich: Cyclopropenylylidene‐stabilized phospheniumcations exhibit the electron richness of classical trialkyl and triaryl phosphines even though they carry a positive charge stemming from a cationic substituent directly bonded to the phosphorous atom. These two facts have been exploited to synthesize gold catalysts that can be easily recycled after use.
Gold(I)-Catalyzed Reactions of Propargyl Esters with Vinyl Derivatives
作者:Christian A. Sperger、Jørn E. Tungen、Anne Fiksdahl
DOI:10.1002/ejoc.201100291
日期:2011.7
A gold-catalyzed olefin cyclopropanation reaction of propargyl esters with vinylester or vinyl sulfonamide derivatives was investigated for the synthesis of highly substituted cyclopropane derivatives in good diastereoselectivity. By varying the vinyl species, trans-cyclopentenyl esters were selectively formed by a formal [3+2] cycloaddition.
An Industrial Perspective on Counter Anions in Gold Catalysis: Underestimated with Respect to “Ligand Effects”
作者:Jasmin Schießl、Jürgen Schulmeister、Angelino Doppiu、Eileen Wörner、Matthias Rudolph、Ralf Karch、A. Stephen K. Hashmi
DOI:10.1002/adsc.201800233
日期:2018.7.4
reactions, representing the key reactivity patterns of goldcatalysis, were analyzed by GC and 1H NMR. The study is focused on establishing of a strategical approach for the consideration of ligand influence and counter anion influence during the catalyst optimization including an industrial perspective. The study shows a dominance of the counter anion, a dominance which up to now has been neglected in
的各种公知的试验反应,代表金催化中的关键反应性模式的转换中,通过GC分析11 H NMR。这项研究的重点是建立一种战略方法,以期在催化剂优化过程中考虑配体影响和抗衡阴离子的影响,包括从工业角度出发。这项研究显示了抗衡阴离子的优势,这一优势迄今为止在大多数常规筛选中都被忽略。此外,剧烈的底物依赖性变得明显,即使底物的微小变化也已经可以强烈影响催化活性并改变最佳的抗衡阴离子或配体。基于收集的数据,提出了一种有效筛选特定底物的战略概念,该概念可作为均相金催化中催化剂优化的重要指导。