1383926-75-7Relevant academic research and scientific papers
Gold-Catalyzed Allenamide [2+2+2]-Cyclotrimerization
Hernández-Díaz, Cristina,Rubio, Eduardo,González, José M.
, p. 265 - 269 (2016)
A protocol involving a gold(I)-catalyzed reaction to elaborate cyclic frames by selective trimerization reactions of N-allenylsulfonamides is reported. Efficiency in the formation of the target [2+2+2] products depends on the concentration of the reagents, the nature of the ancillary ligand on the gold catalyst, and, to a significant extent, on the selection of a low reaction temperature. This singular catalytic allene cycloaddition gives adducts in high isolated yields. In addition to representing a new gold-catalyzed reaction, the reported allenamide cyclotrimerization offers a significant extension to the scant number of allenes that have effectively entered this cyclization mode by use of other metal-catalyzed reactions. Upon aromatization of the assembled adducts, the overall reaction matches the outcome of related and widely investigated alkyne trimerization reactions.
Dynamic Kinetic Resolution in Gold-Catalyzed (4 + 2)-Annulations between Alkynyl Benzaldehydes and Allenamides to Yield Enantioenriched All-Carbon Diarylalkylmethane Derivatives
Pandit, Yashwant Bhaskar,Liu, Rai-Shung
supporting information, p. 548 - 553 (2022/01/20)
This work reports the synthesis of diarylmethane derivatives via gold-catalyzed (4 + 2)-annulations between alkynyl benzaldehydes and allenamides, followed by an aza-Claisen rearrangement. Deuterium labeling and crossover experiments have been performed to confirm this proposed mechanism. With racemic 3-substituted allenamides in a substrate ratio (1:1), we employ chiral gold catalysts to achieve a dynamic kinetic resolution to obtain enantioenriched diarylalkylmethane derivatives with high e.r. levels (up to 93:7).
Ligand-Regulated Palladium-Catalyzed Regiodivergent Hydroarylation of the Distal Double Bond of Allenamides with Aryl Boronic Acid
Dong, Yunhui,Du, Xin,Li, Xinling,Liu, Hui,Liu, Qing,Wang, Ping,Zhang, Daopeng,Zhang, Lizhi,Zhao, Huan
, p. 13276 - 13288 (2021/10/12)
The ligand-regulated regiodivergent hydroarylation of the distal double bond of allenamides with aryl boronic acid was achieved in the presence of palladium(II) catalysts, delivering a variety of functionalized enamide with excellent E selectivity and Markovnikov/anti-Markovnikov selectivity. Two possible coordination intermediates were proposed to be responsible for the regiodivergent hydroarylation: (1) The coordination Intermediate I, which was proposed to be formed through the coordination of MeCN, distal double bond, phenyl to palladium, led to the aryl group away from the Intermediate I, inducing excellent E selectivity and anti-Markovnikov selectivity. (2) A switch of regioselectivity to 1,2-Markovnikov hydroarylation was obtained using bidentate phosphine ligand (dppf or Xantphos). The formed coordination Intermediate II led to the N-tether away from the Intermediate II and at the trans position of aryl, resulting in excellent E selectivity and Markovnikov selectivity. Meanwhile, tentative investigation on the mechanism proved that the hydron source of this hydroarylation is more likely to be boronic acid. The transmetallation between aryl boronic acid and palladium catalyst was the initial step of this transformation.
A palladium-catalyzed regiocontrollable hydroarylation reaction of allenamides with B2pin2/H2O
Cui, Jie,Meng, Long,Chi, Xiaochen,Liu, Qing,Zhao, Pingping,Zhang, Dao-Peng,Chen, Lei,Li, Xinjin,Dong, Yunhui,Liu, Hui
supporting information, p. 4355 - 4358 (2019/04/26)
A novel palladium-catalyzed regiocontrollable hydroarylation reaction of allenamides with B2pin2/H2O has been disclosed. H2O as an ideal hydrogen source was activated by B2pin2 to furnish allylamines or enamines with a broad functional group tolerance. The regioselectivity for both of the two products was up to 99:1 for most of the examples, which was achieved by adjusting the addition order of the catalyst and iodobenzene derivatives. The tentative investigation of the mechanism proved the reaction to be a non-radical process and the deuterium-labeled experiments indicated that the hydrogen was from H2O.
Regioselective 1,2-addition of allenamides with: N -haloimides: Synthesis of 2-halo allylic aminal derivatives
Li, Hong-He,Li, Xiao-Xiao,Zhao, Zhi-Gang,Yuan, Xiao,Sun, Chen-Yang
, p. 4005 - 4013 (2017/07/11)
A strategy for the synthesis of 2-halo allylic aminal derivatives through regioselective 1,2-addition of allenamides with N-haloimides is presented. This reaction was conducted under very mild conditions and gave up to 99% yield. Moreover, the obtained ha
Gold(i) operational in synergistic catalysis for the intermolecular α-addition reaction of aldehydes across allenamides
Ballesteros, Alberto,Morán-Poladura, Pablo,González, Jose M.
supporting information, p. 2905 - 2908 (2016/02/19)
The intermolecular reaction of allenamides with aldehydes is reported. The designed approach relies on gold(i) and organocatalysis for activating the allenamides and the aldehydes respectively. Conditions to achieve an enantioselective version of this int
Phosphite-gold(I)-catalyzed [2+2] intermolecular cycloaddition of enol ethers with N-allenylsulfonamides
Suarez-Pantiga, Samuel,Hernandez-Diaz, Cristina,Piedrafita, Maria,Rubio, Eduardo,Gonzalez, Jose M.
supporting information; experimental part, p. 1651 - 1657 (2012/08/08)
Addition of catalytic amounts of a phosphite-based gold(I) catalyst efficiently triggers the intermolecular [2+2] cycloaddition of allenes and alkenes substituted by electron-donor groups. The reaction is fast and furnishes cyclobutane derivatives in a st
