Rh(1,3-bis(2,4,6-trimethylphenyl)-3,4,5,6-tetrahydropyrimidin-2-ylidene)(COD) tetrafluoroborate, an unsymmetrical Rh-homoazallylcarbene: synthesis, X-ray structure and reactivity in carbonyl arylation and hydrosilylation reactions
作者:Nicolas Imlinger、Klaus Wurst、Michael R. Buchmeiser
DOI:10.1016/j.jorganchem.2004.11.057
日期:2005.10
The synthesis of novel Rh(1,3-bis(2,4,6-trimethylphenyl)-3,4,5,6-tetrahydropyrimidin-2-ylidene)(COD) tetrafluoroborate (1, COD = η4-1,5-cyclooctadiene) is described. The N-heterocyclic carbene acts as a bidentate ligand with the carbene coordinating to the Rh(I) center and an arene group acting as a homoazallyl ligand. 1 was used in various carbonyl arylation and hydrosilylation reactions allowing
Experimental and Computational Studies of the Ruthenium-Catalyzed Hydrosilylation of Alkynes: Mechanistic Insights into the Regio- and Stereoselective Formation of Vinylsilanes
作者:Ruili Gao、Dale R. Pahls、Thomas R. Cundari、Chae S. Yi
DOI:10.1021/om501019j
日期:2014.12.8
regio- and stereoselective hydrosilylation of alkynes to form vinylsilane products. (Z)-Vinylsilane products were selectively formed for sterically nondemanding terminalalkynes, while (E)-vinylsilane products resulted from sterically demanding terminalalkynes. Kinetic data were obtained from the hydrosilylation of phenylacetylene. The phosphine inhibition study showed an uncompetitive Michaelis–Menten
A Selective Synthesis of (E)-Vinylsilanes by Cationic Rhodium Complex-Catalyzed Hydrosilylation of 1-Alkynes and Tandem Hydrosilylation/Isomerization Reaction of Propargylic Alcohols to .beta.-Silyl Ketones
作者:Ryo Takeuchi、Shuichi Nitta、Dai Watanabe
DOI:10.1021/jo00115a020
日期:1995.5
(E)-Vinylsilanes were obtained with high selectivities by [Rh(COD)(2)]BF4/2PPh(3)-catalyzed hydrosilylation of 1-alkynes with triethylsilane. A wide range of 1-alkynes were used. The hydrosilylation of propargylic alcohols with triethylsilane gave (E)-gamma-silyl allylic alcohols 2h-r, a useful source of a chiral alcohol, with high selectivities in excellent yields. The reaction can be carried out without protecting the alcohol functionality. The resulting (E)-gamma-silyl allylic alcohols could be transformed into beta-silyl ketones. The isomerization was also catalyzed by [Rh(COD)(2)]BF4/2PPh(3). Furthermore, the tandem hydrosilylation-isomerization of secondary propargylic alcohols could be carried out in a one-pot procedure.
(E)-丙二烯二硅烷通过使用[Rh(COD)(2)]BF4/2PPh(3)协同催化的水硅化反应获得了高选择性,适用于多种一元炔烃底物。丙炔醇的水硅化反应产生γ-硅基 allylic 醇2h-R,并提供了一种高效产率的构象选择性高的旋多糖醇。该反应无需保护醇的功能性即可进行。由此产生的(E)-γ-硅基 allylic 醇可以通过转化得到β-硅基酮。此外,该[Rh(COD)(2)]BF4/2PPh(3)催化还可以催化丙炔醇的同分异构化反应。Furthermore, a one-pot tandem hydrosilylation-isomerization of secondary propargylic alcohols can be achieved using this approach.
Novel Immobilized Hydrosilylation Catalysts Based on Rhodium 1,3-Bis(2,4,6-trimethylphenyl)-3,4,5,6-tetrahydropyrimidin-2-ylidenes
作者:Nicolas Imlinger、Klaus Wurst、Michael R. Buchmeiser
DOI:10.1007/s00706-004-0255-3
日期:2005.1
were reached. A supported version of 1 was realized by reaction of RhCl( NHC )( COD ) with PS - DVB –CH2–O–CO–CF2–CF2–CF2–COOAg ( PS - DVB = poly(styrene- co -divinylbenzene) to yield PS - DVB –CH2–O–CO–CF2–CF2–CF2–COORh( NHC )( COD ). This supported version of 1 exhibited at least comparable, in some cases increased reactivity compared to 1 and allowed the rapid removal of the catalyst from the reaction
Synthesis and structure of thienyl Fischer carbene complexes of Pt<sup>II</sup> for application in alkyne hydrosilylation
作者:Zandria Lamprecht、Frederick P. Malan、Simon Lotz、Daniela I. Bezuidenhout
DOI:10.1039/d1nj00791b
日期:——
Transmetallation of group 6 thienylene Fischer carbenecomplexes to PtII precursors yielded new examples of neutral platinum(II) bisethoxycarbene complexes with either 2-thienyl (T) or 5-thieno[2,3-b]thienylene (TT) carbene substituents. The use of analogous aminocarbene group 6 precursors proceeded to give isomeric platinum(II) product mixtures where the resultant bisaminocarbene ligands displayed
将第6组亚噻吩菲舍尔卡宾配合物金属化成Pt II前体产生了具有2-噻吩基(T)或5-噻吩并[2,3- b ]亚噻吩基(TT)卡宾取代基的中性铂(II)双乙氧基卡宾配合物的新实例。使用类似的氨基卡宾第6组前驱体可制得同分异构的铂(II)产品混合物,由于空间需求的TT取代基导致围绕Pt-氨基卡宾键的旋转受到限制,所得的双氨基卡宾配体显示出不同的取向。定义明确的Pt II在使用苯乙炔和三乙基硅烷底物的基准氢化硅烷化反应中,将乙氧基卡宾配合物筛选为催化剂前体。观察到对β- E异构体(E)-三乙基(苯乙烯基)硅烷的明显选择性,并且证明(预)催化剂可循环利用,在无溶剂反应中具有活性,并显示出高炔烃官能团耐受性。