119924-83-3Relevant academic research and scientific papers
Photoredox-Catalyzed α-C(sp3)-H Activation of Unprotected Secondary Amines: Facile Access to 1,4-Dicarbonyl Compounds
Zhang, Qian,Huang, Yan,Zhan, Le-Wu,Tang, Wan-Ying,Hou, Jing,Li, Bin-Dong
supporting information, p. 7460 - 7464 (2020/10/09)
A photoredox-catalyzed α-C(sp3)-H activation approach of unprotected secondary amines is reported. Such transformations provide facile access to various 1,4-dicarbonyl compounds using readily available amines and α,β-unsaturated compounds as feedstocks under air conditions. The substrate scope of this method is broad, and a wide array of functional groups are tolerated.
Photochemical generation of acyl and carbamoyl radicals using a nucleophilic organic catalyst: Applications and mechanism thereof
Balletti, Matteo,De Pedro Beato, Eduardo,Mazzarella, Daniele,Melchiorre, Paolo
, p. 6312 - 6324 (2020/08/24)
We detail a strategy that uses a commercially available nucleophilic organic catalyst to generate acyl and carbamoyl radicals upon activation of the corresponding chlorides and anhydrides via a nucleophilic acyl substitution path. The resulting nucleophilic radicals are then intercepted by a variety of electron-poor olefins in a Giese-type addition process. The chemistry requires low-energy photons (blue LEDs) to activate acyl and carbamoyl radical precursors, which, due to their high reduction potential, are not readily prone to redox-based activation mechanisms. To elucidate the key mechanistic aspects of this catalytic photochemical radical generation strategy, we used a combination of transient absorption spectroscopy investigations, electrochemical studies, quantum yield measurements, and the characterization of key intermediates. We identified a variety of off-the-cycle intermediates that engage in a light-regulated equilibrium with reactive radicals. These regulated equilibriums cooperate to control the overall concentrations of the radicals, contributing to the efficiency of the overall catalytic process and facilitating the turnover of the catalyst. This journal is
Acyl Radicals: Intermolecular and Intramolecular Alkene Addition Reactions
Boger, Dale L.,Mathvink, Robert J.
, p. 1429 - 1443 (2007/10/02)
A full study of the use of phenyl selenoesters as precursors to acyl radicals and their subsequent participation in intermolecular and intramolecular alkene addition reactions is detailed.Primary alkyl-, vinyl-, and arylsubstituted acyl radicals generated by Bu3SnH treatment of the corresponding phenyl selenoesters participate cleanly in intermolecular addition reactions with alkenes bearing electron-withdrawing or radical-stabilizing substituents at rates that exceed those of the potentially competitive decarbonylation or reduction.Similarly, their intramolecular addition to activated or unactivated alkenes proceeds without significant competitive reduction or decarbonylation and at rates generally >/= 1 x 106 s-1 with some occuring at rates >/= 3 x 107 s-1.Consistent with their behavior in intermolecular addition reactions, the 5-exo-trig cyclizations of secondary and tertiary alkyl-substituted acyl radicals to an unactivated olefin acceptor may be accompanied by varying degrees of decarbonylation, even under low-temperature free-radical conditions.Studies are presented which suggest that the intramolecular additions of acyl radicals to alkenes under the conditions detailed herein may be regarded as irreversible, kinetically controlled processes which exhibit regioselectivity that is predictable based on well-established empirical rules set forth for the analogous free-radical cyclization reactions of alkyl radicals.
Phenyl Selenoesters as Effective Precursors of Acyl Radicals for Use in Intermolecular Alkene Addition Reactions
Boger, Dale L.,Mathvink, Robert J.
, p. 1777 - 1779 (2007/10/02)
The scope of the use of phenyl selenoesters as effective precursors to acyl radicals for use in intermolecular olefin addition reactions is detailed.
