Catalytic Asymmetric C–H Insertions of Rhodium(II) Azavinyl Carbenes
摘要:
A highly efficient enantioselective C-H insertion of azavinyl carbenes into unactivated alkanes has been developed. These transition metal carbenes are directly generated from readily available and stable 1-sulfonyl-1,2,3-triazoles in the presence of chiral Rh(II) carboxylates and are used for C-H functionalization of alkanes to access a variety of beta-chiral sulfonamides.
Catalytic Asymmetric C–H Insertions of Rhodium(II) Azavinyl Carbenes
摘要:
A highly efficient enantioselective C-H insertion of azavinyl carbenes into unactivated alkanes has been developed. These transition metal carbenes are directly generated from readily available and stable 1-sulfonyl-1,2,3-triazoles in the presence of chiral Rh(II) carboxylates and are used for C-H functionalization of alkanes to access a variety of beta-chiral sulfonamides.
Catalytic Asymmetric Synthesis of Pyrroloindolines via a Rhodium(II)-Catalyzed Annulation of Indoles
作者:Jillian E. Spangler、Huw M. L. Davies
DOI:10.1021/ja4025337
日期:2013.5.8
Herein we report the synthesis of pyrroloindolines via a catalytic enantioselective formal [3+2] cycloaddition of C(3)-substituted indoles. This methodology utilizes 4-aryl-1-sulfonyl-1,2,3-triazoles as carbenoid precursors and the rhodium(II)-tetracarboxylate catalyst Rh2(S-PTAD)4. A variety of aryl-substituted pyrroloindolines were prepared in good yields and with high levels of enantioinduction
<i>N</i>-Imidazolylation of Sulfoximines from<i>N</i>-Cyano Sulfoximines, 1-Alkynes, and<i>N</i>-Sulfonyl Azides
作者:Sanghyuck Kim、Ji Eun Kim、Jinsub Lee、Phil Ho Lee
DOI:10.1002/adsc.201500636
日期:2015.11.16
The rhodium-catalyzed N-imidazolylation of N-sulfonyl-1,2,3-triazoles with a variety of N-cyano sulfoximines has been developed for the synthesis of N-imidazolyl sulfoximines via elimination of molecular nitrogen. Copper-catalyzed [3+2] cycloaddition followed by rhodium-catalyzed N-imidazolylation from 1-alkynes, N-sulfonylazides, and N-cyano sulfoximines is also demonstrated for the synthesis of N-imidazolyl
Generation of Functionalized Azepinone Derivatives via a (4 + 3)-Cycloaddition of Vinyl Ketenes and α-Imino Carbenes Derived from <i>N</i>-Sulfonyl-triazoles
作者:Harrison M. Hill、Zachary D. Tucker、Kevin X. Rodriguez、Katelyn A. Wendt、Brandon L. Ashfeld
DOI:10.1021/acs.joc.1c03002
日期:2022.3.4
3)-cycloaddition between vinyl ketenes and N-sulfonyl-1,2,3-triazoles for the construction of azepinone products is described. Employing vinyl ketenes as a 1,4-dipolar surrogate, instead of the more commonly used dienyl moieties, allows for the intermolecular and selective formation of azepinone products over a potential (3 + 2)-cycloadduct under mild reaction conditions allows for the generation of azepinone products
Rhodium-Catalyzed Intermolecular C–H Functionalization as a Key Step in the Synthesis of Complex Stereodefined β-Arylpyrrolidines
作者:Robert W. Kubiak、Huw M. L. Davies
DOI:10.1021/acs.orglett.8b01362
日期:2018.7.6
The synthesis of beta-arylpyrrolidines via a catalytic enantioselective intermolecular allylic C(sp)(3)-H functionalization of trans-alkenes followed by immediate reduction, ozonolysis, and then in situ diversification of the resulting cyclic hemiaminal to furnish highly substituted, stereoenriched beta-arylpyrrolidines is reported. This methodology utilizes 4-aryl-1-sulfony1-1,2,3-triazoles as carbene precursors and the dirhodium tetracarboxylate catalyst Rh-2(S-NTTL)(4). A variety of beta-arylpyrrolidines were prepared in good yields with high levels of diastereo- and enantioselectivity over four linear steps, requiring only a single purification procedure.