14485-09-7Relevant articles and documents
Visible-Light-Mediated Heterocycle Functionalization via Geometrically Interrupted [2+2] Cycloaddition
Alegre-Requena, Juan V.,Mekereeya, Aroonroj,Paton, Robert S.,Popescu, Mihai V.,Smith, Martin D.
, p. 23020 - 23024 (2020)
The [2+2] photocycloaddition is the most valuable and intensively investigated photochemical process. Here we demonstrate that irradiation of N-acryloyl heterocycles with blue LED light (440 nm) in the presence of an IrIII complex leads to efficient and high yielding fused γ-lactam formation across a range of substituted heterocycles. Quantum calculations show that the reaction proceeds via cyclization in the triplet excited state to yield a 1,4-diradical; intersystem crossing leads preferentially to the closed shell singlet zwitterion. This is geometrically restricted from undergoing recombination to yield a cyclobutane by the planarity of the amide substituent. A prototropic shift leads to the observed bicyclic products in what can be viewed as an interrupted [2+2] cycloaddition.
Pyridine-Enabled C-N Bond Activation for the Rapid Construction of Amides and 4-Pyridylglyoxamides by Cooperative Palladium/Copper Catalysis
Song, Liangliang,Claessen, Sander,Van Der Eycken, Erik V.
, p. 8045 - 8054 (2020/07/15)
A pyridine-enabled C-N bond activation of peptidomimetics employing cooperative palladium/copper catalysis in water is developed. Diverse amides and 4-pyridylglyoxamides are simultaneously synthesized through two steps from commercially available materials in a rapid, environmentally friendly, and high atom-economical manner.
Palladium-Catalyzed Regioselective Hydroaminocarbonylation of Alkynes to α,β-Unsaturated Primary Amides with Ammonium Chloride
Ji, Xiaolei,Gao, Bao,Zhou, Xibing,Liu, Zongjian,Huang, Hanmin
, p. 10134 - 10141 (2018/07/09)
α,β-Unsaturated primary amides have found numerous applications in drug development, organic materials, and polymer sciences. However, the catalytic synthesis of α,β-unsaturated primary amides via carbonylation of alkynes has long been an elusive endeavor. Here, we report a novel palladium-catalyzed hydroaminocarbonylation of alkynes with NH4Cl as the amine source, enabling the highly chemo- and regioselective synthesis of α,β-unsaturated primary amides. A variety of alkynes, including aromatic alkynes, aliphatic alkynes, terminal alkynes, internal alkynes, as well as diynes with various functional groups, react well. The method turns the parasitic noncoordination ability of ammonium salts into a strategic advantage, enabling the gram-scale reaction to be performed in the presence of 0.05 mol % of catalyst with excellent selectivity.