01529nas a2200169   4500008004100000245010700041210006900148260000800217300001400225490000700239520088800246100002001134700003201154700001801186700003101204856012401235       2017                        eng d00aGeneral nickel-catalyzed method for C-H bond alkynylation of heteroarenes through chelation assistance0 aGeneral nickelcatalyzed method for CH bond alkynylation of heter  cFEB  a2907-29140 v233 a<p>A general nickel-catalyzed method for the alkynylation of heteroarenes through monodentate chelation assistance is described. Many heterocycles, including indoles, pyrroles, imidazoles and pyrazole, efficiently coupled with (triisopropylsilyl)alkynyl bromide, and synthetically important functional groups, such as halides, ether, nitrile, nitro were tolerated. Synthetic applicability of this Ni-catalyzed method is demonstrated by the removal of triisopropylsilyl (-SiiPr₃) group, and further functionalization into triazolyl, benzofuranyl and alkynyl arene derivatives. Preliminary mechanistic investigations on the alkynylation of indole suggest that the reaction proceeds through kinetically relevant C-H activation and follows the two-electron redox pathway. A catalytically competent Ni-species, [(Phen)₃Ni].NiBr₄ has been isolated and structurally characterized.</p>1 aPunji, Benudhar1 aKhake, Shrikant, manmathapp1 aSoni, Vineeta1 aGonnade, Rajesh, Ghanshyam  uhttps://library.ncl.res.in/content/general-nickel-catalyzed-method-c-h-bond-alkynylation-heteroarenes-through-chelation