1383926-75-7Relevant articles and documents
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.
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.
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
