Pd‐Catalyzed Dearomatization of Anthranils with Vinylcyclopropanes by [4+3] Cyclization Reaction
作者:Qiang Cheng、Jia‐Hao Xie、Yue‐Cheng Weng、Shu‐Li You
DOI:10.1002/anie.201901251
日期:2019.4.16
Dearomatization of anthranils with vinylcyclopropanes (VCPs) by Pd‐catalyzed [4+3] cyclization reaction has been realized. In the presence of a catalytic amount of borane as an activator, bridged cyclic products were obtained in good to excellent yields with excellent stereoselectivities. By introducing a chiral PHOX ligand (L5), asymmetric dearomatization reactions of anthranils with vinylcyclopropanes
Palladium(0)-Catalyzed Dearomatization of 2-Nitrobenzofurans through Formal (3+2) Cycloadditions with Vinylcyclopropanes: A Straightforward Access to Cyclopenta[b]benzofurans
palladium-catalyzed dearomatization of electron-poor arenes, we report herein that various 2-nitrobenzofurans efficiently undergo a dearomative (3+2) cycloaddition with vinylcyclopropanes. This new method gives access to a wide variety of cyclopenta[b]benzofuran derivatives in a straightforward manner.
photoredox-promoted and nitrogen radical catalyzed [3 + 2] cyclization of vinylcyclopropanes and N-tosyl vinylaziridines with alkenes is developed. Key to the success of this process is the use of the readily tunable hydrazone as a nitrogen radical catalyst. Preliminary mechanism studies suggest that the photogenerated nitrogen radical undergoes reversibleradical addition to the vinylcyclopropanes
Rhodium(<scp>iii</scp>)-catalyzed C–H/C–C activation sequence: vinylcyclopropanes as versatile synthons in direct C–H allylation reactions
作者:Jia-Qiang Wu、Zhi-Ping Qiu、Shang-Shi Zhang、Jing-Gong Liu、Ye-Xing Lao、Lian-Quan Gu、Zhi-Shu Huang、Juan Li、Honggen Wang
DOI:10.1039/c4cc07839j
日期:——
Succession of C-Hactivation and C-Cactivation was achieved by using a single rhodium(III) catalyst. Vinylcyclopropanes were used as versatile coupling partners. Mechanistic studies suggest that the olefin insertion step is rate-determining and a facile beta-carbon elimination is involved, which represents a novel ring opening mode of vinylcyclopropanes.
A straightforward entry to chiral carbocyclic nucleoside analogues is achievedviathe enantioselective [3+2] cycloaddition of α-nucleobase substituted acrylates to vinyl cyclopropanes.