63511-95-5Relevant academic research and scientific papers
Dimethylzinc-Initiated Radical Coupling of β-Bromostyrenes with Ethers and Amines
Solvhoj, Amanda,Ahlburg, Andreas,Madsen, Robert
, p. 16272 - 16279 (2015/11/03)
A new coupling reaction has been developed in which β-bromostyrenes react with ethers and tertiary amines to introduce the styryl group in the α-position. The transformation is mediated by Me2Zn/O2 with 10 % MnCl2 and is believed to proceed by a radical addition-elimination mechanism. The ether and the amine are employed as solvent and the coupling takes place through the most stable α radical for unsymmetrical substrates. The products are obtained in moderate to good yields as the pure E isomers. The coupling can be achieved with a range of smaller cyclic and acyclic ethers/amines as well as various substituted β-bromostyrenes.
Regioselective heck vinylation of electron-rich olefins with vinyl halides: Is the neutral pathway in operation?
McConville, Matthew,Saidi, Ourida,Blacker, John,Xiao, Jianliang
experimental part, p. 2692 - 2698 (2009/08/15)
Highly regioselective vinylation of electron-rich olefins by bromo- as well as chlorostyrenes is effected by palladium catalysis with either mono- or bidentate phosphines in a molecular solvent, with no need for halide scavengers, ionic liquids, or ionic additives. The use of the hemilabile 1,3-bis(diphenylphosphino)propane monoxide (dpppO) as a ligand led to faster reactions of more challenging 2-substituted vinyl ethers and reduced Pd loadings. In contrast to the related arylation reaction, evidence suggests that the vinylation may proceed via the neutral Heck mechanism.
The rapid photomediated alkenylation of 2-alkyl-1,3-dioxolanes with alkynes: A stereoelectronically assisted chain reaction
Geraghty, Niall W. A.,Lally, Andrea
, p. 4300 - 4302 (2007/10/03)
The photomediated reaction of alkynes such as DMAD with 1,3-dioxolanes leads to remarkably rapid alkenylation; evidence is presented that these reactions occur via a chain mechanism. The Royal Society of Chemistry 2006.
A general model for selectivity in olefin cross metathesis
Chatterjee, Arnab K.,Choi, Tae-Lim,Sanders, Daniel P.,Grubbs, Robert H.
, p. 11360 - 11370 (2007/10/03)
In recent years, olefin cross metathesis (CM) has emerged as a powerful and convenient synthetic technique in organic chemistry; however, as a general synthetic method, CM has been limited by the lack of predictability in product selectivity and stereoselectivity. Investigations into olefin cross metathesis with several classes of olefins, including substituted and functionalized styrenes, secondary allylic alcohols, tertiary allylic alcohols, and olefins with α-quaternary centers, have led to a general model useful for the prediction of product selectivity and stereoselectivity in cross metathesis. As a general ranking of olefin reactivity in CM, olefins can be categorized by their relative abilities to undergo homodimerization via cross metathesis and the susceptibility of their homodimers toward secondary metathesis reactions. When an olefin of high reactivity is reacted with an olefin of lower reactivity (sterically bulky, electron-deficient, etc.), selective cross metathesis can be achieved using feedstock stoichiometries as low as 1:1. By employing a metathesis catalyst with the appropriate activity, selective cross metathesis reactions can be achieved with a wide variety of electron-rich, electron-deficient, and sterically bulky olefins. Application of this model has allowed for the prediction and development of selective cross metathesis reactions, culminating in unprecedented three-component intermolecular cross metathesis reactions.
A novel approach of cycloaddition of difluorocarbene to α-β-unsaturated aldehydes and ketones: Synthesis of gem-difluorocyclopropyl ketones and 2-fluorofurans
Xu, Wei,Chen, Qing-Yun
, p. 1151 - 1156 (2007/10/03)
A series of gem-difluorocyclopropyl acetals and ketals are easily obtained in moderate yields from the [1 + 2] cycloaddition of difluorocarbene to 1,3-dioxolanes of α,β-unsaturated aromatic aldehydes and ketones. Hydrolysis of these fluorinated compounds under acidic conditions either gives the corresponding gem-difluorocyclopropyl ketones or 1-aryl-2-fluorofuran derivatives through intramolecular carbonium rearrangement with simultaneous ring cleavage.
Ruthenium-catalyzed olefin cross metathesis of styrenes as an alternative to the Heck and cross-coupling reactions
Chatterjee, Arnab K.,Toste, F. Dean,Choi, Tae-Lim,Grubbs, Robert H.
, p. 634 - 637 (2007/10/03)
The use of olefin cross metathesis as a method for the formation of styrenyl-olefins is described using allylic substituted olefins and electron-deficient olefins. These methods provide an orthogonal method to alternative olefination strategies, such as the Heck reaction. These methods have also been employed in the total synthesis of 3-flavanols.
