N-Acyloxyphthalimides as Nitrogen Radical Precursors in the Visible Light Photocatalyzed Room Temperature C–H Amination of Arenes and Heteroarenes
摘要:
This paper reports a room temperature visible light photocatalyzed method for the C-H amination of arenes and heteroarenes. A key enabling advance in this work is the design of N-acyloxyphthalimides as precursors to nitrogen-based radical intermediates for these transformations. A broad substrate scope is presented, including the selective meta-amination of pyridine derivatives. A radical aromatic substitution mechanism is proposed.
A phosphonium ylide as a visible light organophotoredox catalyst
作者:Yasunori Toda、Katsumi Tanaka、Riki Matsuda、Tomoyuki Sakamoto、Shiho Katsumi、Masahiro Shimizu、Fuyuki Ito、Hiroyuki Suga
DOI:10.1039/d1cc00996f
日期:——
A phosphonium ylide-based visible light organophotoredox catalyst has been designed and successfully applied to halohydrin synthesis using trichloroacetonitrile and epoxides. An oxidative quenching cycle by the ylide catalyst was established, which was confirmed by experimental mechanistic studies.
Nitrogen-centered radical-mediated C–H imidation of arenes and heteroarenes <i>via</i> visible light induced photocatalysis
作者:Hyejin Kim、Taehoon Kim、Dong Gil Lee、Sang Weon Roh、Chulbom Lee
DOI:10.1039/c4cc03905j
日期:——
The C-H imidation of arenes and heteroarenes has been achieved via visible light induced photocatalysis. In the presence of an iridium(III) photoredox catalyst, the reaction of aromatic substrates with N-chlorophthalimide furnishes the N-aryl products at room temperature through a nitrogen-centered radical mediated aromatic substitution.
In this study, a visible-light-induced intermolecular C-H bond imidation of arenes was achieved at ambient condition. By using simple phthalimide with (diacetoxyiodo)benzene and molecular iodine, direct metal-/photocatalyst-free C-N bond formation was achieved. The imidation protocol was designed by using time-dependent density functional theory calculations and experimentally demonstrated for 28 substrates
Visible-Light-Driven C–H Imidation of Arenes and Heteroarenes by a Phosphonium Ylide Organophotoredox Catalyst: Application to C–H Functionalization of Alkenes
作者:Yasunori Toda、Toya Kobayashi、Fumiya Hirai、Takamichi Yano、Makoto Oikawa、Kimiya Sukegawa、Masahiro Shimizu、Fuyuki Ito、Hiroyuki Suga
DOI:10.1021/acs.joc.3c00988
日期:2023.7.7
Phosphonium ylide catalysis through an oxidative quenching cycle has been developed for visible-light-driven C–H imidation of arenes and heteroarenes. The present protocol could be applied not only to trihalomethylative lactonization reactions involving trifluoromethyl, trichloromethyl, and tribromomethyl radicals but also to the first example of an organophotoredox-catalyzed imidative lactonization