01654nas a2200181   4500008004100000022001400041245011100055210006900166260000900235300001400244490000700258520099100265100002301256700002301279700002401302700002001326856012601346       2022                        eng d  a2044-475300aRoom temperature Z-selective hydrogenation of alkynes by hemilabile and non-innocent (NNN)Co(ii) catalysts0 aRoom temperature Zselective hydrogenation of alkynes by hemilabi  cMAR   a1843-18490 v123 a<p>
	Hemilabile and phosphine-free quinolinyl-based NNN-type pincer and non-pincer cobalt complexes were developed for the room temperature catalytic transfer semi-hydrogenation of alkynes to Z-alkenes. Treatment of the quinolinyl-amine ligand, [C9H6N(NH)CH2CH2NEt2] ((NNN2NEt2)-N-Q-N-CH)-H with CoX2 afforded the pincer complexes kappa(3)-((NNN2NEt2)-N-Q-N-CH)CoX2 (X = Cl, Br), whereas, the quinolinyl-amide ligand, [C9H6N(NH)C(O)CH2NEt2] ((NNNNEt2)-N-Q-N-C(O))-H gave chelate anionic complexes kappa(2)-((NN)-N-Q)CoX2((NHNEt2)-H-C(O)) (X = Cl, Br). The well-defined anionic non-pincer cobalt complexes efficiently catalyzed the semi-hydrogenation of diverse alkynes to deliver highly chemoselective and stereodivergent Z-alkenes at room temperature. This hydrogenation exhibited broad substrate scope with the tolerance of sensitive functional groups, such as -Cl, -Br, -I, -OH, -NH2, -COOMe, and pyridinyl, employing a stable and user-friendly ammonia borane hydrogen source.</p>
1 aSharma, Dipesh, M.1 aGouda, Chandrakant1 aGonnade, Rajesh, G.1 aPunji, Benudhar  uhttps://library.ncl.res.in/content/room-temperature-z-selective-hydrogenation-alkynes-hemilabile-and-non-innocent-nnncoii02102nas a2200289   4500008004100000022001400041245013100055210006900186260000800255300001400263490000700277520110200284653001301386653003201399653002901431653002101460653002101481653001901502100002601521700002301547700002501570700002301595700002501618700001701643700002501660856012701685       2024                        eng d  a2155-543500aDehydrogenative coupling of alcohols with internal alkynes under nickel catalysis: an access to β-deuterated branched ketones0 aDehydrogenative coupling of alcohols with internal alkynes under  cMAY  a8294-83090 v143 a<p>
	In synthetic organic chemistry, unconventional strategies for advanced chemical synthesis pose interesting and challenging problems. Alcohols act as alkylating agents in the C-C and C-N bond-forming reactions via the dehydrogenative borrowing hydrogen strategy in traditional transition metal catalysis; however, as an acylating agent in the C-C bond-forming reactions is challenging and rarely reported. Here, we report the dehydrogenative coupling of benzylic alcohols with internal alkynes under nickel(II) catalysis, wherein alcohol is used as an acylating agent. This reaction system affords a wide range of alpha-branched aryl ketone derivatives with zero waste generation through the umpolung borrowing hydrogen strategy. Moreover, we have demonstrated the chemodivergent applications of the alpha-disubstituted ketones to other valuable building blocks, including large-scale synthesis of beta-deuterated branched ketones. Several spectroscopic studies, intermediate identification, and density functional theory calculations were performed to elucidate the reaction mechanism.</p>
10aAlcohols10aalpha-branched aryl ketones10adehydrogenative coupling10ainternal alkynes10anickel catalysis10apseudoumpolung1 aSubaramanian, Murugan1 aGouda, Chandrakant1 aRoy, Triptesh, Kumar1 aGanesan, Sivakumar1 aBanerjee, Subhrashis1 aVanka, Kumar1 aBalaraman, Ekambaram  uhttps://library.ncl.res.in/content/dehydrogenative-coupling-alcohols-internal-alkynes-under-nickel-catalysis-access-%CE%B2