Increasing the Structural Span of Alkyne Metathesis
作者:Peter Persich、Josep Llaveria、Rudy Lhermet、Teresa de Haro、Robert Stade、Azusa Kondoh、Alois Fürstner
DOI:10.1002/chem.201302320
日期:2013.9.23
new generation of alkyne metathesis catalysts, which are distinguished by high activity and an exquisite functional group tolerance, allows the scope of this transformation to be extended beyond its traditional range. They accept substrates that were previously found problematic or unreactive, such as propargyl alcohol derivatives, electron‐deficient and electron‐rich acetylenes of various types, and
作者:Birte Haberlag、Matthias Freytag、Constantin G. Daniliuc、Peter G. Jones、Matthias Tamm
DOI:10.1002/anie.201207772
日期:2012.12.21
Now even terminal: The 2,4,6‐trimethylbenzylidyne complexes [MesCMOC(CF3)2Me}3] (M=Mo, W) were synthesized from [Mo(CO)6] and [W(CO)6], respectively. The molybdenum complex is an efficient catalyst for the metathesis of internal and terminalalkynes and also for the ring‐closing metathesis of internal and terminal α,ω‐diynes at room temperature and low catalyst concentrations.
Efficient catalytic alkyne metathesis with a fluoroalkoxy-supported ditungsten(III) complex
作者:Henrike Ehrhorn、Janin Schlösser、Dirk Bockfeld、Matthias Tamm
DOI:10.3762/bjoc.14.220
日期:——
The catalytic alkyne metathesis activity of these metal complexes was determined in the self-metathesis, ring-closing alkyne metathesis and cross-metathesis of internal and terminal alkynes, revealing an almost equally high metathesis activity for the bimetallic tungstencomplex W2F3 and the alkylidyne complex W Ph F3. In contrast, Mo2F6 displayed no significant activity in alkyne metathesis.
Tuning the Catalytic Alkyne Metathesis Activity of Molybdenum and Tungsten 2,4,6-Trimethylbenzylidyne Complexes with Fluoroalkoxide Ligands OC(CF<sub>3</sub>)<sub><i>n</i></sub>Me<sub>3–<i>n</i></sub> (<i>n</i> = 0–3)
作者:Celine Bittner、Henrike Ehrhorn、Dirk Bockfeld、Kai Brandhorst、Matthias Tamm
DOI:10.1021/acs.organomet.7b00519
日期:2017.9.11
The molybdenum and tungsten 2,4,6-trimethylbenzylidyne complexes [MesC≡MOC(CF3)nMe3–n}3] (M = Mo: MoF0, n = 0; MoF3, n = 1; MoF6, n = 2; MoF9, n = 3; M = W: WF3, n = 1; Mes = 2,4,6-trimethylphenyl) were prepared by the reaction of the tribromides [MesC≡MBr3(dme)] (dme = 1,2-dimethoxyethane) with the corresponding potassium alkoxides KOC(CF3)nMe3–n. The molecular structures of all complexes were established
钼和钨2,4,6-三甲基苄二炔络合物[MesC≡MOC(CF 3)n Me 3– n } 3 ](M = Mo:MoF0,n = 0;MoF3,n = 1;MoF6,n= 2;MoF 9,n= 3; M = W:WF 3,n= 1; Mes = 2,4,6-三甲基苯基)通过三溴化物[MesC 3 MBr 3(dme)](dme = 1)反应制备。,2-二甲氧基乙烷)和相应的烷氧基钾KOC(CF 3)n Me 3– n。通过X射线衍射分析确定了所有配合物的分子结构。研究了在内部和末端炔烃的复分解和闭环炔烃复分解反应中生成的亚烷基配合物的催化活性,显示出对烷氧化物配体氟含量的强烈依赖性。通过涉及2-丁炔的复分解模型反应的DFT计算合理化了不同的催化性能。由于计算结果预测了通过增加氟化度可稳定金属环丁二烯(MCBD)中间体,因此用3-己炔处理MoF9可得到MCBD配合物[(C 3 Et 3)Mo
Preparation of Imidazolin-2-iminato Molybdenum and Tungsten Benzylidyne Complexes: A New Pathway to Highly Active Alkyne Metathesis Catalysts
作者:Birte Haberlag、Xian Wu、Kai Brandhorst、Jörg Grunenberg、Constantin G. Daniliuc、Peter G. Jones、Matthias Tamm
DOI:10.1002/chem.201000597
日期:2010.8.2
excess of 3‐hexyne. Complexes 3 a and 3 b are able to efficiently catalyse alkyne cross metathesis of various 3‐pentynyl benzyl ethers5 and benzoic esters 7 at room temperature, to afford 2‐butyne and the corresponding diethers 6 and diesters 8. The tungsten complex 3 a proved to be a superior catalyst for ring‐closing alkyne metathesis, and the [10]cyclophanes 10 and 12 were synthesised in high yield
的反应〔PhCMBr 3(DME)](DME = 1,2-二甲氧基乙烷)与六氟叔丁醇盐的LiX或KX [X = OC(CF 3)2本人]得到benzylidyne配合物[PhCMX 3(dme)](2 a:M = W,2 b:M = Mo),它进一步与锂试剂Li(Im t Bu N)反应,该试剂由MeLi由1,3-二叔丁基咪唑啉-生成-2-亚胺(IM吨卜NH),以形成咪唑啉-2- iminato配合物[PhCMX 2(IM吨卜N)](3:M = W,3b中:M =钼)。丙炔复合物[EtCMoX2(NIm t Bu)](4)通过用过量的3-己炔处理3 b得到。配合物3a和3b能够在室温下有效催化各种3-戊炔基苄基醚5和苯甲酸酯7的炔烃交叉复分解反应,得到2-丁炔和相应的二醚6和二酯8。钨配合物3a被证明是闭环炔烃复分解的优良催化剂,[10]环烷10和12是由1,3-双(3-戊炔氧基甲