α-Aminoxy-Acid-Auxiliary-Enabled Intermolecular Radical γ-C(sp<sup>3</sup>
)−H Functionalization of Ketones
作者:Heng Jiang、Armido Studer
DOI:10.1002/anie.201712066
日期:2018.2.5
site‐specific intermolecular γ‐C(sp3)−H functionalization of ketones has been developed using an α‐aminoxy acid auxiliary applying photoredox catalysis. Regioselective activation of an inert C−H bond is achieved by 1,5‐hydrogen atom abstraction by an oxidatively generated iminyl radical. Tertiary and secondary C‐radicals thus formed at the γ‐position of the imine functionality undergo radicalconjugate addition
of iminyl radical‐triggered 1,5‐hydrogen atom transfer and (5+2) or (5+1) annulation processes, a series of structurally novel and interesting azepine and spiro‐tetrahydropyridine derivatives have been successfully prepared in moderate to good yields. This method utilizes FeCl2 as the catalyst and readily available oximes as five‐atom units, while showcasing broad substrate scope and good functional
Photoinduced Remote Functionalisations by Iminyl Radical Promoted C−C and C−H Bond Cleavage Cascades
作者:Elizabeth M. Dauncey、Sara P. Morcillo、James J. Douglas、Nadeem S. Sheikh、Daniele Leonori
DOI:10.1002/anie.201710790
日期:2018.1.15
A photoinduced cascade strategy leading to a variety of differentially functionalised nitriles and ketones has been developed. These reactions rely on the oxidative generation of iminyl radicals from simple oximes. Radical transposition by C(sp3 )-(sp3 ) and C(sp3 )-H bond cleavage gives access to distal carbon radicals that undergo SH 2 functionalisations. These mild, visible-light-mediated procedures
Iron‐Catalyzed Synthesis of Dihydronaphthalenones from Aromatic Oxime Esters
作者:Youcan Zhang、Zhiping Yin、Xiao‐Feng Wu
DOI:10.1002/adsc.201900283
日期:2019.7.2
radical‐mediated synthesis of dihydronaphthalenones from oxime esters has been developed. By using iron salt as a green and inexpensive catalyst, various α‐aryl oxime esters were transformed into the corresponding dihydronaphthalenones in moderate to good yields with high chemo‐selectivities. The reaction proceeds via 1,5‐hydrogen atom transfer and then intramolecular radical cyclization sequence.
作者:Pramod Rai、Kakoli Maji、Sayan K. Jana、Biplab Maji
DOI:10.1039/d2sc04005k
日期:——
three-dimensional molecular topology from flat-aromatic compounds. However, severe reactivity and selectivity issues make this process arduous. Herein, we describe visible-light energy-transfer catalysis for the intermolecular dearomative [4 + 2] cycloaddition reaction of feedstock naphthalene molecules with vinyl benzenes. Tolerating a wide range of functional groups, structurally diverse 2-acyl naphthalenes and