A decarboxylative approach for regioselective hydroarylation of alkynes
作者:Jing Zhang、Ruja Shrestha、John F. Hartwig、Pinjing Zhao
DOI:10.1038/nchem.2602
日期:2016.12
group that activates one of several aromatic C–H bonds. Here we report a new catalytic method for regioselective alkyne hydroarylation with benzoicacid derivatives during which the carboxylate functionality directs the alkyne to the ortho-C–H bond with elimination in situ to form a vinylarene product. The decarboxylation stage of this tandem sequence is envisioned to proceed with the assistance of
Rhodium- and Iridium-Catalyzed Oxidative Coupling of Benzoic Acids with Alkynes via Regioselective C−H Bond Cleavage
作者:Kenji Ueura、Tetsuya Satoh、Masahiro Miura
DOI:10.1021/jo070735n
日期:2007.7.1
coupling of benzoicacids with internal alkynes effectively proceeds in the presence of [Cp*RhCl2]2 and Cu(OAc)2·H2O as catalyst and oxidant, respectively, to produce the corresponding isocoumarin derivatives. The copper salt can be reduced to a catalytic quantity under air. Interestingly, by using [Cp*IrCl2]2 in place of [Cp*RhCl2]2, the substrates undergo 1:2 coupling accompanied by decarboxylation to afford
Simple, convenient, and direct conversion of anilines and anilides into arynes
作者:B. Baigrie、J. I. G. Cadogan、J. R. Mitchell、A. K. Robertson、J. T. Sharp
DOI:10.1039/p19720002563
日期:——
Reaction of aniline with pentyl nitrite and acetic anhydride in benzene, or other solvents, gives benzyne in up to 32% yield as measured by trapping with anthracene, and tetraphenylcyclopentadienone and its 2,5-di-p-tolyl analogue. The role of the anhydride is to by-pass the suppressive effect of water on benzyne formation from the diazonium acetate ion pair. Reaction in benzene of aniline–acetic anhydride
Palladium nanoparticles and sodium acetate catalyze the reaction of aryl bromide with diarylacetylene to produce annulated products in good yield. One equivalent of PEG-600 serves as the solvent. This procedure is compatible with a wide variety of functional groups.
The rhodium-catalyzed oxidative 1:2 coupling reactions of arylboronic acids or their esters with alkynes smoothly proceed to produce the corresponding annulated products. Of special note, highly substituted, readily soluble, and tractable anthracene and tetracene derivatives can be obtained selectively from 2-naphthyl- and 2-anthrylboron reagents, respectively.