38100-40-2Relevant academic research and scientific papers
Preparation of N-nitrohydroxylamines by substitutive nitration
Khodot,Petrova,Anikin,Chlenov
, p. 231 - 233 (1996)
Interaction of Na- or K-salts of N-acetyl-N-methylhydroxylamines with acyl or aryl halides results in corresponding O-substituted N-acetyl-N-methylhydroxyiamines. Nitration of these compounds by nitronium salts or dinitrogen pentoxide results in O-substit
Late-Stage Photoredox C-H Amidation of N-Unprotected Indole Derivatives: Access to N-(Indol-2-yl)amides
Weng, Yue,Ding, Bo,Liu, Yunqing,Song, Chunlan,Chan, Lo-Ying,Chiang, Chien-Wei
supporting information, p. 2710 - 2714 (2021/05/05)
The late-stage functionalization of N-unprotected indoles can be useful for modifying low-molecular-weight drugs and bioactive peptides. Whereas indole carboxamides are valuable in pharmaceutical applications, the preparation N-(indol-2-yl)amides with similar structures continues to be challenging. Herein we report on visible-light-induced late-stage photoredox C-H amidation with N-unprotected indoles and tryptophan-containing peptides, leading to the formation of N-(indol-2-yl)amide derivatives. N-Unprotected indoles and aryloxyamides that contain an electron-withdrawing group could be coupled directly to eosin Y as the photocatalyst by irradiation with a green light-emitting diode at room temperature. Mechanistic studies and density functional theory calculations indicate that the transformation might proceed through the oxidative C-H functionalization of indole with a PS? to PS?- cycle. This protocol provides a new toolkit for the late-stage modification labeling and peptide-drug conjugation of N-unprotected indole derivatives.
Regioselective Intramolecular Allene Amidation Enabled by an EDA Complex**
Liu, Lu,Ward, Robert M.,Schomaker, Jennifer M.
supporting information, p. 13783 - 13787 (2020/10/06)
The addition of radicals to unsaturated precursors is a powerful tool for the synthesis of both carbo- and heterocyclic organic building blocks. The recent advent of mild ways to generate N-centered radicals has reignited interest in exploiting highly regio-, chemo-, and stereoselective transformations that employ these reactive intermediates. While the additions of aminyl, iminyl, and amidyl radicals to alkenes and alkynes have been well-studied, analogous additions to allenes are scarce. Allenes offer several attractive features, including potential for selective amidation at three distinct sites via judicious choice of precursor or radical source, the opportunity for axial-to-point chirality transfer, and productive trapping of vinyl or allyl radical intermediates to diversify functionality in the products. In this article, we report a regioselective addition of amidyl radicals to allenes to furnish an array of valuable N-heterocycle scaffolds.
Visible-Light-Mediated Synthesis of Amidyl Radicals: Transition-Metal-Free Hydroamination and N-Arylation Reactions
Davies, Jacob,Svejstrup, Thomas D.,Fernandez Reina, Daniel,Sheikh, Nadeem S.,Leonori, Daniele
supporting information, p. 8092 - 8095 (2016/07/16)
The development of photoredox reactions of aryloxy-amides for the generation of amidyl radicals and their use in hydroamination-cyclization and N-arylation reactions is reported. Owing to the ease of single-electron-transfer reduction of the aryloxy-amides, the organic dye eosin Y was used as the photoredox catalyst, which results in fully transition-metal-free processes. These transformations exhibit a broad scope, are tolerant to several important functionalities, and have been used in the late-stage modification of complex and high-value N-containing molecules.
