Functional Metathesis Catalyst Through Ring Closing Enyne Metathesis: One Pot Protocol for Living Heterotelechelic Polymers
作者:Subhajit Pal、Fiorella Lucarini、Albert Ruggi、Andreas F. M. Kilbinger
DOI:10.1021/jacs.7b12805
日期:2018.3.7
Enyne ring closing metathesis has been used to synthesize functional group carrying metathesiscatalysts from a commercial (Ru-benzylidene) Grubbs' catalysts. The new Grubbs-type ruthenium carbene was used to synthesize living heterotelechelic ROMP polymers without any intermediate purification. Olefinmetathesis with a mono substituted alkyne followed by ring closing metathesis with an allylic ether
New phenoxybenzylidene ruthenium chelates were synthesised from the second generation Grubbs catalysts bearing a triphenylphosphine ligand (or its para-substituted analogues) by metathesis exchange with substituted 2-vinylphenols. The complexes behave like a latentcatalyst and are characterized by an improved catalytic behaviour as compared to that of the known analogues, i.e., they exhibit high catalytic
作者:Saswata Gupta、Siyuan Su、Yu Zhang、Peng Liu、Donald J. Wink、Daesung Lee
DOI:10.1021/jacs.1c02237
日期:2021.5.19
demonstrated them as an aromatic equivalent of the Grubbs-type ruthenium alkylidene catalysts. These ruthenabenzenes can be prepared via an enyne metathesis and metallotropic [1,3]-shift cascade process to form alkyne-chelated ruthenium alkylidene intermediates followed by spontaneous cycloaromatization. The aromatic nature of these complexes was confirmed by spectroscopic and X-ray crystallographic data
金属芳烃构成了一类独特的芳族化合物,其中一种或多种过渡金属元素结合到芳族体系中,其母体是金属苯。与碳原型相比,金属苯的主要关注点之一通常涉及与其相对芳香性相关的结构特征。含过渡金属的金属苯也涉及某些催化过程,例如炔烃复分解聚合;然而,这些基于过渡金属的金属芳族化合物尚未开发为催化剂。在此,我们描述了一种生成多种钌苯的有效策略,并将它们证明为 Grubbs 型钌亚烷基催化剂的芳族等价物。这些钌苯可以通过烯炔复分解和金属化[1,3]-移位级联工艺制备,形成炔烃螯合的亚烷基钌中间体,然后自发环芳构化。这些配合物的芳香性质通过光谱和 X 射线晶体学数据得到证实,并通过 DFT 计算研究了环芳构化过程的机理途径。这些钌苯对复分解和其他转化表现出强大的催化活性,这说明金属苯不仅是具有结构和理论意义的化合物,而且还是开发新催化剂的新平台。这些配合物的芳香性质通过光谱和 X 射线晶体学数据得到证实,并通过
One‐Step Ring Opening Metathesis Block‐Like Copolymers and their Compositional Analysis by a Novel Retardation Technique
作者:Mohammad Yasir、Peng Liu、Jens C. Markwart、Oksana Suraeva、Frederik R. Wurm、Jansie Smart、Marco Lattuada、Andreas F. M. Kilbinger
DOI:10.1002/anie.202005366
日期:2020.8.3
synthesized using G3 by first allowing the consumption of the mixture of M1 and M2 and then adding M1 again. In addition, in order to measure the fast reaction rates of the G3 catalyst with M1 , we report a novel retardation technique based on an unusual reversible G3 Fischer‐carbene to G3 benzylidene/alkylidene transformation.
The Discovery of Quinoxaline-Based Metathesis Catalysts from Synthesis of Grazoprevir (MK-5172)
作者:Michael J. Williams、Jongrock Kong、Cheol K. Chung、Andrew Brunskill、Louis-Charles Campeau、Mark McLaughlin
DOI:10.1021/acs.orglett.6b00070
日期:2016.5.6
Olefin metathesis (OM) is a reliable and practical synthetic methodology for challenging carbon–carbon bond formations. While existing catalysts can effect many of these transformations, the synthesis and development of new catalysts is essential to increase the application breadth of OM and to achieve improved catalyst activity. The unexpected initial discovery of a novel olefin metathesis catalyst