Metal-Free Photochemical Imino-Alkylation of Alkenes with Bifunctional Oxime Esters.

The concurrent installation of C-C and C-N bonds across alkene frameworks represents a powerful tool to prepare motifs that are ubiquitous in pharmaceuticals and bioactive compounds. To construct such prevalent bonds, most alkene difunctionalization methods demand the use of precious metals or activated alkenes. We report a metal-free, photochemically mediated imino-alkylation of electronically diverse alkenes to install both alkyl and iminyl groups in a highly efficient manner. The exceptionally mild reaction conditions, broad substrate scope, excellent functional group tolerance, and facile one-pot reaction protocol highlight the utility of this method to prepare privileged motifs from readily available alkene and acid feedstocks. One key and striking feature of this transformation is that an electrophilic trifluoromethyl radical is equally efficient with both electron-deficient and electron-rich alkenes. Additionally, dispersion-corrected density functional theory (DFT) and empirical investigations provide detailed mechanistic insight into this reaction.

[1]  Y. Gong,et al.  Cu-Catalyzed C(sp3)–N Coupling and Alkene Carboamination Enabled by Ligand-Promoted Selective Hydrazine Transfer to Alkyl Radicals , 2022, ACS Catalysis.

[2]  K. Hirano,et al.  Hydroamination, Aminoboration, and Carboamination with Electrophilic Amination Reagents: Umpolung-Enabled Regio- and Stereoselective Synthesis of N-Containing Molecules from Alkenes and Alkynes. , 2022, Journal of the American Chemical Society.

[3]  C. Schindler,et al.  Reactivity of oximes for diverse methodologies and synthetic applications , 2022, Nature Synthesis.

[4]  N. Jiao,et al.  Radical 1,4/5-Amino Shift Enables Access to Fluoroalkyl-Featured Primary β(γ)-Aminoketones under Metal-Free Conditions. , 2021, Angewandte Chemie.

[5]  James J. Douglas,et al.  Copper-catalysed amination of alkyl iodides enabled by halogen-atom transfer , 2021, Nature Catalysis.

[6]  Qiu Wang,et al.  Copper-Catalyzed 1,2-Aminocyanation of Unactivated Alkenes via Cyano Migration. , 2020, Organic letters.

[7]  N. Shibata,et al.  Contribution of Organofluorine Compounds to Pharmaceuticals , 2020, ACS omega.

[8]  Kranthi Kumar Gangu,et al.  A Review on Recent Advances in Nitrogen-Containing Molecules and Their Biological Applications , 2020, Molecules.

[9]  F. Glorius,et al.  Photosensitized Intermolecular Carboimination of Alkenes through the Persistent Radical Effect , 2019, Angewandte Chemie.

[10]  A. Studer,et al.  The Persistent Radical Effect in Organic Synthesis. , 2019, Angewandte Chemie.

[11]  E. Cho,et al.  Reactivity Tuning for Radical–Radical Cross-Coupling via Selective Photocatalytic Energy Transfer: Access to Amine Building Blocks , 2019, ACS Catalysis.

[12]  Lin Zhu,et al.  Copper-Catalyzed Radical Aminotrifluoromethylation of Alkenes. , 2019, Journal of the American Chemical Society.

[13]  F. Glorius,et al.  Visible-Light Photosensitized Aryl and Alkyl Decarboxylative Carbon-Heteroatom and Carbon-Carbon Bond Formations , 2019 .

[14]  M. Kassiou,et al.  Cubanes in Medicinal Chemistry. , 2018, Journal of medicinal chemistry.

[15]  C. Feng,et al.  Intermolecular Carboamination of Unactivated Alkenes. , 2018, Journal of the American Chemical Society.

[16]  Hao Xu,et al.  Iron(II)-Catalyzed Azidotrifluoromethylation of Olefins and N-Heterocycles for Expedient Vicinal Trifluoromethyl Amine Synthesis. , 2018, ACS catalysis.

[17]  N. Meanwell Fluorine and Fluorinated Motifs in the Design and Application of Bioisosteres for Drug Design. , 2018, Journal of medicinal chemistry.

[18]  D. Leonori,et al.  Photoredox Imino Functionalizations of Olefins , 2017, Angewandte Chemie.

[19]  Xinhao Zhang,et al.  Iron-Catalyzed Carboamination of Olefins: Synthesis of Amines and Disubstituted β-Amino Acids. , 2017, Journal of the American Chemical Society.

[20]  N. Jiao,et al.  Azidofluoroalkylation of Alkenes with Simple Fluoroalkyl Iodides Enabled by Photoredox Catalysis. , 2017, Organic letters.

[21]  Peng Liu,et al.  Catalytic Intermolecular Carboamination of Unactivated Alkenes via Directed Aminopalladation. , 2017, Journal of the American Chemical Society.

[22]  S. Luo,et al.  Oxidative 1,2-carboamination of alkenes with alkyl nitriles and amines toward γ-amino alkyl nitriles , 2017, Nature Communications.

[23]  F. Glorius,et al.  Unnatural Amino Acid Synthesis Enabled by the Regioselective Cobalt(III)-Catalyzed Intermolecular Carboamination of Alkenes. , 2016, Angewandte Chemie.

[24]  T. Loh,et al.  Visible-Light-Promoted Carboimination of Unactivated Alkenes for the Synthesis of Densely Functionalized Pyrroline Derivatives , 2016 .

[25]  B. Tan,et al.  A Dual-Catalytic Strategy To Direct Asymmetric Radical Aminotrifluoromethylation of Alkenes. , 2016, Journal of the American Chemical Society.

[26]  W. R. Dolbier,et al.  Direct Photoredox-Catalyzed Reductive Difluoromethylation of Electron-Deficient Alkenes. , 2015, Chemistry.

[27]  T. Rovis,et al.  Rh-Catalyzed Intermolecular Syn-Carboamination of Alkenes via a Transient Directing Group , 2015, Nature.

[28]  M. D. Hill,et al.  Applications of Fluorine in Medicinal Chemistry. , 2015, Journal of medicinal chemistry.

[29]  M. Sodeoka,et al.  Aminotrifluoromethylation of olefins via cyclic amine formation: mechanistic study and application to synthesis of trifluoromethylated pyrrolidines. , 2015, Journal of the American Chemical Society.

[30]  V. Dembitsky Naturally occurring bioactive Cyclobutane-containing (CBC) alkaloids in fungi, fungal endophytes, and plants. , 2014, Phytomedicine : international journal of phytotherapy and phytopharmacology.

[31]  G. Masson,et al.  Photoredox-induced three-component azido- and aminotrifluoromethylation of alkenes. , 2014, Organic letters.

[32]  E. Carreira,et al.  Four-membered ring-containing spirocycles: synthetic strategies and opportunities. , 2014, Chemical reviews.

[33]  Guillaume Dagousset,et al.  Photoredox-induced three-component oxy-, amino-, and carbotrifluoromethylation of enecarbamates. , 2014, Organic letters.

[34]  Fei Wang,et al.  Copper-catalyzed intermolecular trifluoromethylazidation of alkenes: convenient access to CF3 -containing alkyl azides. , 2014, Angewandte Chemie.

[35]  Durga Prasad Hari,et al.  The photoredox-catalyzed Meerwein addition reaction: intermolecular amino-arylation of alkenes. , 2014, Angewandte Chemie.

[36]  G. Fumagalli,et al.  Oxyarylation and aminoarylation of styrenes using photoredox catalysis. , 2013, Organic letters.

[37]  M. Akita,et al.  Intermolecular aminotrifluoromethylation of alkenes by visible-light-driven photoredox catalysis. , 2013, Organic letters.

[38]  Q. Zhang,et al.  Copper-catalyzed intermolecular aminocyanation and diamination of alkenes. , 2013, Angewandte Chemie.

[39]  H. Miyabe,et al.  Polarity-mismatched addition of electrophilic carbon radicals to an electron-deficient acceptor: cascade radical addition-cyclization-trapping reaction. , 2012, The Journal of organic chemistry.

[40]  S. Stahl,et al.  Palladium(II)-catalyzed alkene functionalization via nucleopalladation: stereochemical pathways and enantioselective catalytic applications. , 2011, Chemical reviews.

[41]  C. Humblet,et al.  Escape from flatland: increasing saturation as an approach to improving clinical success. , 2009, Journal of medicinal chemistry.

[42]  T. Müller,et al.  Hydroamination: direct addition of amines to alkenes and alkynes. , 2008, Chemical reviews.

[43]  F. Diederich,et al.  Fluorine in Pharmaceuticals: Looking Beyond Intuition , 2007, Science.

[44]  S. Chemler,et al.  Heterocycle synthesis by copper facilitated addition of heteroatoms to alkenes, alkynes and arenes. , 2007, Chemical Society reviews.

[45]  I. Ryu,et al.  Radicals masquerading as electrophiles: dual orbital effects in nitrogen-philic acyl radical cyclization and related addition reactions. , 2007, Accounts of chemical research.

[46]  Martin Stahl,et al.  Fluorine in Medicinal Chemistry , 2004, Chembiochem : a European journal of chemical biology.

[47]  J. N. Johnston,et al.  The first azacyclopentenyl carbinyl radical isomerizations (ACCRI): independent use of steric and electronic (polarization) effects as gating elements. , 2003, Journal of the American Chemical Society.

[48]  H. Fischer The persistent radical effect: a principle for selective radical reactions and living radical polymerizations. , 2001, Chemical reviews.