2108-54-5Relevant articles and documents
1,3-Alkyl Transposition in Allylic Alcohols Enabled by Proton-Coupled Electron Transfer
Knowles, Robert R.,Seidler, Gesa,Zhao, Kuo
supporting information, p. 20190 - 20195 (2021/08/13)
A method is described for the isomerization of acyclic allylic alcohols into β-functionalized ketones via 1,3-alkyl transposition. This reaction proceeds via light-driven proton-coupled electron transfer (PCET) activation of the O?H bond in the allylic al
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
Nickel-Catalyzed Coupling of Arylzinc Halides with Thioesters
Gehrtz, Paul H.,Kathe, Prasad,Fleischer, Ivana
, p. 8774 - 8778 (2018/06/26)
The Pd-catalyzed Fukuyama reaction of thioesters with organozinc reagents is a mild, functional-group-tolerant method for acylation chemistry. Its Ni-catalyzed variant might be a sustainable alternative to expensive catalytic Pd sources. We investigated the reaction of S-ethyl thioesters with aryl zinc halides with hetero- and homotopic Ni precatalysts and several ligands. The results show that both homo- and heterotopic species may contribute to catalysis. The substrate scope using an operationally homogeneous defined Ni complex was established. Acyl radicals are postulated as short-lived intermediates.
