Pd-Catalyzed Highly Regio- and Stereoselective Formation of C–C Double Bonds: An Efficient Method for the Synthesis of Benzofuran-, Dihydrobenzofuran-, and Indoline-Containing Alkenes
A highly regio- and stereoselective C–C double bond formation reactionvia Pd-catalyzed Heck-type cascade process with N-tosylhydrazones has been developed. Various N-tosylhydrazones derived from both ketones and aldehydes are found to be efficient substrates to provide di- and trisubstitutedolefins with high regio- and stereoselectivity. Furthermore, this reaction has a good functional group tolerance
Transition-metal-catalyzed cross-coupling reactions between naturally abundant sp3-hybridized carbon centers facilitate access to diverse molecules with complex three-dimensional structures. Organometallic compounds are among one of the most powerful reagents that are broadly used in carbon–carbon bondformations. Although sp2-hybridized organometallic compounds are widely employed in cross-couplings, sp3-hybridized
Mechanism of the Ullmann Biaryl Ether Synthesis Catalyzed by Complexes of Anionic Ligands: Evidence for the Reaction of Iodoarenes with Ligated Anionic Cu<sup>I</sup> Intermediates
作者:Ramesh Giri、Andrew Brusoe、Konstantin Troshin、Justin Y. Wang、Marc Font、John F. Hartwig
DOI:10.1021/jacs.7b11853
日期:2018.1.17
characterized by a combination of 19F NMR, 1H NMR, and UV-vis spectroscopy, as well as ESI-MS. The heteroleptic complexes generated in situ react with iodoarenes to form biarylethers in high yields without evidence for an aryl radical intermediate. Measurements of 13C/12C isotope effects showed that oxidative addition of the iodoarene occurs irreversibly. This information, in combination with the kinetic
Copper(I) Phenoxide Complexes in the Etherification of Aryl Halides
作者:Jesse W. Tye、Zhiqiang Weng、Ramesh Giri、John F. Hartwig
DOI:10.1002/anie.200902245
日期:2010.3.15
No copping out! Copper(I) phenoxidecomplexes containing chelating ligands (see picture), proposed intermediates in copper‐catalyzed etherification of arylhalides, have been synthesized and fully characterized. The kinetic and chemical competence of the isolated complexes are demonstrated for the synthesis of aryl phenyl ethers, and experiments provide evidence against mechanistic pathways involving
irradiation in the presence of catalytic amounts of [(DPEphos)(bcp)Cu]PF6 and an amine, a range of unactivated aryl and alkyl halides were shown to be smoothly activated through a rare Cu(I)/Cu(I)*/Cu(0) catalytic cycle. This complex efficiently catalyzes a series of radical processes, including reductions, cyclizations, and direct arylation of arenes.