Urethanes synthesis from oxamic acids under electrochemical conditions
作者:Ikechukwu Martin Ogbu、Jonathan Lusseau、Gülbin Kurtay、Frédéric Robert、Yannick Landais
DOI:10.1039/d0cc05069e
日期:——
Urethanesynthesis via oxidative decarboxylation of oxamic acids under mild electrochemical conditions is reported. This simple phosgene-free route to urethanes involves an in situ generation of isocyanates by anodic oxidation of oxamic acids in an alcoholic medium. The reaction is applicable to a wide range of oxamic acids, including chiral ones, and alcohols furnishing the desired urethanes in a
The generation of carbamoyl radicals, followed by their addition to heteroarenes, was performed under mild conditions through a metal-free photocatalyzed decarboxylation of oxamic acids. The process has been applied to the carbamoylation of heteroaromatic bases using α-aminoacid-derived oxamic acids, leading to the corresponding amides without racemization.
based on a photocatalyzed oxidative decarboxylation of oxamic acids is described. The reaction includes in situ generation of an isocyanate from the oxamic acid, using an organic dye as a photocatalyst, a hypervalent iodine reagent as an oxidant and a light source, which trigger the free-radical decarboxylation. This protocol successfully avoids the isolation, purification and storage of carcinogenic
Photocatalyzed decarboxylation of oxamic acids under near-infrared conditions
作者:Ikechukwu Martin Ogbu、Dario M. Bassani、Frédéric Robert、Yannick Landais
DOI:10.1039/d2cc03155h
日期:——
Photocatalyzed oxidative decarboxylation of oxamic acids under near-infrared irradiation using Os(bptpy)2(PF6)2 as catalyst is reported. The reaction was applied to the synthesis of urethanes and heterocyclic amides. Mechanistic studies and comparative penetration depths between the NIR and the visiblelight mediated processes are discussed.
Iron-Catalyzed Oxidative Decarboxylation of Oxamic Acids: A Safe and Efficient Photochemical Route to Urethanes
作者:Yannick Landais、Gülbin Kurtay、Jonathan Lusseau、Frédéric Robert
DOI:10.1055/a-2131-3368
日期:2024.2
This study presents a facile method for synthesizing urethanes through the photocatalyzed oxidative decarboxylation of oxamic acids. The process involves the formation of an isocyanate in situ from an oxamic acid under blue-light irradiation (427 nm) in the presence of ferrocene as a photocatalyst, 2-picolinic acid as a ligand, and potassium bromate as an oxidant. The one-pot procedure effectively avoids