We present an allylic polyfluoroarylation reaction with broad substrate scope and excellent functional group tolerance, using organozinc reagents under mild conditions. A catalytic amount of triphenylphosphine oxide efficiently promotes iodine-zinc exchange reaction between polyfluoroaryl iodide and dimethylzinc, and the resulting phosphine oxide-activated polyfluoroarylzinc undergoes substitution reaction with allylic halides to afford the corresponding polyfluoroarylated products. (C) 2015 Elsevier Ltd. All rights reserved.
(XPhos) catalytic system was developed for C–H allylation of polyfluoroarenes with allylic pivalates. The reactions showed excellent functional-group tolerance, good yields, and high regioselectivities. Mechanistic investigations supported a (π-allyl)palladium complex pathway through a directed oxidative addition of the allylic pivalate to palladium, followed by sequential nucleophilic attack by the polyfluorobenzene
Regio- and Stereoselective Allylic C–H Arylation with Electron-Deficient Arenes by 1,1′-Bi-2-naphthol–Palladium Cooperation
作者:Gang-Wei Wang、An-Xi Zhou、Shi-Xia Li、Shang-Dong Yang
DOI:10.1021/ol501247b
日期:2014.6.6
A palladium-catalyzedallylic C–H arylation reaction with electron-deficient arenes with high regio- and stereoselectivity is reported. This work represents the first successful use of 1,1′-bi-2-naphthol as the ancillary ligand in allylic C–H activation, which is the key factor for chemoselectivity. Furthermore, high selectivity allylic C–H acetoxylation and amination were also successfully achieved
Copper- and Phosphine-Ligand-Free Palladium-Catalyzed Direct Allylation of Electron-Deficient Polyfluoroarenes with Allylic Chlorides
作者:Yan-Bo Yu、Shilu Fan、Xingang Zhang
DOI:10.1002/chem.201202824
日期:2012.11.12
copper‐ and phosphine‐ligand‐free Pd‐catalyzed directallylation of electron‐deficient polyfluoroarenes with allylicchlorides and the reaction mechanism are described (see scheme). The simple catalytic system, broad substrate scope, and excellent functional‐group compatibility of this protocol provides a useful and facile access to allylated polyfluoroarenes.
Synthesis of Allylarenes<i>via</i>Catalytic Decarboxylation of Allyl Benzoates
作者:Kai F. Pfister、Matthias F. Grünberg、Lukas J. Gooßen
DOI:10.1002/adsc.201400624
日期:2014.11.3
AbstractA catalyst system consisting of the palladium(0) complex Pd2(dba)3 and tri(p‐tolyl)phosphine was found to efficiently promote the decarboxylation of allyl benzoates with formation of allylarenes. This catalytic CO activation followed by extrusion of carbon dioxide and CC bond formation represents a sustainable alternative to traditional waste‐intensive cross‐couplings. The scope of the transformation includes allyl and cinnamyl esters of various ortho‐substituted benzoic acids. For particularly activated substrates, the palladium catalyst can optionally be replaced by an inexpensive nickel complex.magnified image