Anodic benzylic C(sp<sup>3</sup>)–H amination: unified access to pyrrolidines and piperidines
作者:Sebastian Herold、Daniel Bafaluy、Kilian Muñiz
DOI:10.1039/c8gc01411f
日期:——
important heterocyclic motifs of pyrrolidines and piperidines within a uniform reaction protocol. The mechanism of this unprecedented C–H amination strategy involves anodic C–H activation to generate a benzylic cation, which is efficiently trapped by a nitrogen nucleophile. The applicability of the process is demonstrated for 40 examples comprising both 5- and 6-membered ring formations.
Sulfonamide-Directed Chemo- and Site-Selective Oxidative Halogenation/Amination Using Halogenating Reagents Generated in Situ from Cyclic Diacyl Peroxides
作者:Denghu Chang、Rong Zhao、Congyin Wei、Yuan Yao、Yang Liu、Lei Shi
DOI:10.1021/acs.joc.8b00243
日期:2018.3.16
The combination of cyclicdiacylperoxides with commercially available halide salts as a unique halogenating system is utilized in Hofmann–Löffler–Freytag-type reaction. This strategy allows for the formation of N-chloroamides, δ-brominated products, and even biologically relevant pyrrolidines under mild conditions in moderate to excellent yields. Meanwhile, the preliminary structure of the in situ
oxidation catalysis employing bromine has remained largely unexplored. We herein show that the combination of a tetraalkylammonium bromide and meta‐chloroperbenzoic acid offers a unique catalyst system for the convenient and selective oxidation of saturated C(sp3)−H bonds upon photochemical initiation with day light. This approach enables remote, intramolecular, position‐selective C−H amination as demonstrated
and ecologically benign alternatives to transition metals, although their application as molecular catalysts in challenging CH oxidation reactions has remained elusive. An attractive iodine oxidation catalysis is now shown to promote the convenient conversion of carbon–hydrogenbonds into carbon–nitrogen bonds with unprecedented complete selectivity. The reaction proceeds by two interlocked catalytic
Remote azidation of C(sp<sup>3</sup>)–H bonds to synthesize δ-azido sulfonamides<i>via</i>iron-catalyzed radical relay
作者:Kang-Jie Bian、Cheng-Yu Wang、Yu-Ling Huang、Yi-Hao Xu、Xi-Sheng Wang
DOI:10.1039/d0ob00964d
日期:——
as a radical initiator and terminator, we report a selective remote C–H functionalization to access δ-azido sulfonamides through a radicalrelay process. The reaction of N-fluorosulfonamide furnishes the corresponding products in excellent yields with high regioselective control. The key to success is the highly efficient iron-mediated redox azido transfer to the in situ generated carbon radical. The