Hf(IV)-Catalyzed Enantioselective Epoxidation of <i>N</i>-Alkenyl Sulfonamides and <i>N</i>-Tosyl Imines
作者:José Luis Olivares-Romero、Zhi Li、Hisashi Yamamoto
DOI:10.1021/ja211880s
日期:2012.3.28
Asymmetric epoxidation of allylic and homoallylic amine derivatives catalyzed by Hf(IV)-bishydroxamic acid complexes is described. Under similar conditions, aldimine and ketimine produced oxaziridines. The sulfonyl group is demonstrated to be an effective directing group for these transformations.
Gold-Catalyzed Intramolecular Aminoarylation of Alkenes: CC Bond Formation through Bimolecular Reductive Elimination
作者:William E. Brenzovich、Diego Benitez、Aaron D. Lackner、Hunter P. Shunatona、Ekaterina Tkatchouk、William A. Goddard、F. Dean Toste
DOI:10.1002/anie.201002739
日期:——
Gold‐ilocks and the 3 mol % catalyst: Bimetallic gold bromides allow the room temperature aminoarylation of unactivated terminal olefins with aryl boronic acids using Selectfluor as an oxidant. A catalytic cycle involving gold(I)/gold(III) and a bimolecular reductive elimination for the key CC bond‐forming step is proposed. dppm= bis(diphenylphosphanyl)methane.
Copper-catalyzed N-arylation of tert-butyl N-sulfonylcarbamates with diaryliodonium salts at room temperature
作者:Soo-Yeon Moon、Moonjee Koh、Kris Rathwell、Seo-Hee Jung、Won-Suk Kim
DOI:10.1016/j.tet.2015.01.032
日期:2015.3
A new and mild synthetic approach for the synthesis of N-arylsulfonamides under copper-catalyzed conditions at room temperature has been developed. The reaction employs various tert-butyl N-sulfonylcarbamates and diaryliodoniumsalts to avoid potential genotoxic impurities. A one-pot coupling/Boc-deprotection sequence is also reported to provide mono N-arylsulfonamides in good to excellent yields.
Copper-Catalyzed Si–H Bond Insertion Reaction of <i>N</i>-Propargyl Ynamides with Hydrosilanes
作者:En-He Huang、Ying-Qi Zhang、Da-Qiu Cui、Xin-Qi Zhu、Xiao Li、Long-Wu Ye
DOI:10.1021/acs.orglett.1c03830
日期:2022.1.14
Transition-metal-catalyzed Si–H bondinsertion reactions are generally limited to stabilized diazo compounds. An efficient copper-catalyzed Si–H bondinsertion reaction of N-propargyl ynamides with hydrosilanes is described, allowing practical and atom-economic construction of valuable organosilanes in generally moderate to excellent yields under mild reaction conditions. Notably, this reaction constitutes
Ligand Bite Angle-Dependent Palladium-Catalyzed Cyclization of Propargylic Carbonates to 2-Alkynyl Azacycles or Cyclic Dienamides
作者:David S. B. Daniels、Alison S. Jones、Amber L. Thompson、Robert S. Paton、Edward A. Anderson
DOI:10.1002/anie.201309162
日期:2014.2.10
palladium‐catalyzed cyclization of propargyliccarbonates with sulfonamide nucleophiles is critically dependent on the bite angle of the bidentate phosphine ligand. Ligands with small bite angles favor attack on the central carbon atom of an allenylpalladium intermediate to afford cyclicdienamide products, whereas the use of those with large bite angles leads to alkynyl azacycles, with high stereoselectivity