Direct and Practical Synthesis of Primary Anilines through Iron-Catalyzed C–H Bond Amination

The direct C–H amination of arenes is an important strategy to streamline the discovery and preparation of functional molecules. Herein, we report an operationally simple arene C–H amination reaction that, in contrast to most literature precedent, affords directly the synthetically versatile primary aniline products without relying on protecting group manipulations. Inexpensive Fe(II)-sulfate serves as a convenient catalyst for the transformation. The reaction tolerates a wide scope of arenes, including structurally complex drugs. Importantly, the arene substrates are used as limiting reagents in the transformation. This operationally simple transformation should considerably accelerate the discovery of medicines and functional molecules.

[1]  Sukbok Chang,et al.  (NHC)Cu-Catalyzed Mild C-H Amidation of (Hetero)arenes with Deprotectable Carbamates: Scope and Mechanistic Studies. , 2016, Journal of the American Chemical Society.

[2]  J. Falck,et al.  Dirhodium-catalyzed C-H arene amination using hydroxylamines , 2016, Science.

[3]  K. Miyamoto,et al.  Direct Hydroxylation and Amination of Arenes via Deprotonative Cupration. , 2016, Journal of the American Chemical Society.

[4]  Ian W. Davies,et al.  Aryl amination using ligand-free Ni(II) salts and photoredox catalysis , 2016, Science.

[5]  D. Leonori,et al.  Visible-Light-Mediated Synthesis of Amidyl Radicals: Transition-Metal-Free Hydroamination and N-Arylation Reactions. , 2016, Journal of the American Chemical Society.

[6]  T. Ritter,et al.  Charge Transfer Directed Radical Substitution Enables para-Selective C–H Functionalization , 2016, Nature chemistry.

[7]  T Gensch,et al.  Mild metal-catalyzed C-H activation: examples and concepts. , 2016, Chemical Society reviews.

[8]  K. Rauch,et al.  Ketone-Assisted Ruthenium(II)-Catalyzed C–H Imidation: Access to Primary Aminoketones by Weak Coordination , 2016 .

[9]  K. Itami,et al.  Catalytic Methods for Aromatic C–H Amination: An Ideal Strategy for Nitrogen-Based Functional Molecules , 2016 .

[10]  B. Morandi,et al.  Direct Catalytic Synthesis of Unprotected 2-Amino-1-Phenylethanols from Alkenes by Using Iron(II) Phthalocyanine. , 2016, Angewandte Chemie.

[11]  David A. Nicewicz,et al.  Site-selective arene C-H amination via photoredox catalysis , 2015, Science.

[12]  Sukbok Chang,et al.  Transition-metal-catalyzed C-N bond forming reactions using organic azides as the nitrogen source: a journey for the mild and versatile C-H amination. , 2015, Accounts of chemical research.

[13]  Preston M. MacQueen,et al.  Nickel-catalyzed monoarylation of ammonia. , 2015, Angewandte Chemie.

[14]  T. Kawakami,et al.  Catalytic C-H imidation of aromatic cores of functional molecules: ligand-accelerated Cu catalysis and application to materials- and biology-oriented aromatics. , 2015, Journal of the American Chemical Society.

[15]  A. Studer,et al.  N-aminopyridinium salts as precursors for N-centered radicals--direct amidation of arenes and heteroarenes. , 2015, Organic letters.

[16]  K. Okano,et al.  Copper-mediated aromatic amination reaction and its application to the total synthesis of natural products. , 2014, Chemical communications.

[17]  Hao Xu,et al.  Iron(II)-Catalyzed Intermolecular Amino-Oxygenation of Olefins through the N–O Bond Cleavage of Functionalized Hydroxylamines , 2014, Journal of the American Chemical Society.

[18]  Hyejin Kim,et al.  Nitrogen-centered radical-mediated C-H imidation of arenes and heteroarenes via visible light induced photocatalysis. , 2014, Chemical communications.

[19]  L. Ackermann,et al.  Weakly Coordinating Directing Groups for Ruthenium(II)‐ Catalyzed CH Activation , 2014 .

[20]  M. Sanford,et al.  N-Acyloxyphthalimides as Nitrogen Radical Precursors in the Visible Light Photocatalyzed Room Temperature C–H Amination of Arenes and Heteroarenes , 2014, Journal of the American Chemical Society.

[21]  Martin D. Eastgate,et al.  A Mild, Ferrocene-Catalyzed C–H Imidation of (Hetero)Arenes , 2014, Journal of the American Chemical Society.

[22]  E. Nakamura,et al.  Synthesis of anthranilic acid derivatives through iron-catalyzed ortho amination of aromatic carboxamides with N-chloroamines. , 2014, Journal of the American Chemical Society.

[23]  J. Falck,et al.  Direct Stereospecific Synthesis of Unprotected N-H and N-Me Aziridines from Olefins , 2014, Science.

[24]  T. Ritter,et al.  Pd-catalyzed aryl C-H imidation with arene as the limiting reagent. , 2013, Journal of the American Chemical Society.

[25]  D. Blackmond,et al.  Radical-based regioselective C-H functionalization of electron-deficient heteroarenes: scope, tunability, and predictability. , 2013, Journal of the American Chemical Society.

[26]  L. Tran,et al.  Directed amination of non-acidic arene C-H bonds by a copper-silver catalytic system. , 2013, Angewandte Chemie.

[27]  J. Hartwig,et al.  Sterically controlled, palladium-catalyzed intermolecular amination of arenes. , 2013, Journal of the American Chemical Society.

[28]  Hao Xu,et al.  Iron(II)-catalyzed intramolecular aminohydroxylation of olefins with functionalized hydroxylamines. , 2013, Journal of the American Chemical Society.

[29]  J. Falck,et al.  Elusive metal-free primary amination of arylboronic acids: synthetic studies and mechanism by density functional theory. , 2012, Journal of the American Chemical Society.

[30]  J. O. Bauer,et al.  Organocatalytic, oxidative, intermolecular amination and hydrazination of simple arenes at ambient temperature. , 2012, Organic letters.

[31]  J. Morken,et al.  Direct stereospecific amination of alkyl and aryl pinacol boronates. , 2012, Journal of the American Chemical Society.

[32]  T. Mei,et al.  Weak coordination as a powerful means for developing broadly useful C-H functionalization reactions. , 2012, Accounts of chemical research.

[33]  J. Hartwig,et al.  On the interpretation of deuterium kinetic isotope effects in C-H bond functionalizations by transition-metal complexes. , 2012, Angewandte Chemie.

[34]  Brenton DeBoef,et al.  Metal-free intermolecular oxidative C-N bond formation via tandem C-H and N-H bond functionalization. , 2011, Journal of the American Chemical Society.

[35]  Sukbok Chang,et al.  Intermolecular oxidative C-N bond formation under metal-free conditions: control of chemoselectivity between aryl sp2 and benzylic sp3 C-H bond imidation. , 2011, Journal of the American Chemical Society.

[36]  A. Stepan,et al.  Divergent C-H functionalizations directed by sulfonamide pharmacophores: late-stage diversification as a tool for drug discovery. , 2011, Journal of the American Chemical Society.

[37]  C. Fischer,et al.  Palladium- and copper-mediated N-aryl bond formation reactions for the synthesis of biological active compounds , 2011, Beilstein journal of organic chemistry.

[38]  Melanie S Sanford,et al.  Palladium-catalyzed ligand-directed C-H functionalization reactions. , 2010, Chemical reviews.

[39]  M. Beller,et al.  Recent Applications of Palladium‐Catalyzed Coupling Reactions in the Pharmaceutical, Agrochemical, and Fine Chemical Industries , 2009 .

[40]  P. Baran,et al.  Protecting-group-free synthesis as an opportunity for invention. , 2009, Nature chemistry.

[41]  Yuyang Jiang,et al.  Easy copper-catalyzed synthesis of primary aromatic amines by couplings aromatic boronic acids with aqueous ammonia at room temperature. , 2009, Angewandte Chemie.

[42]  Stuart L. Schreiber,et al.  Organic chemistry: Molecular diversity by design , 2009, Nature.

[43]  M. Taillefer,et al.  A very simple copper-catalyzed synthesis of anilines by employing aqueous ammonia. , 2009, Angewandte Chemie.

[44]  S. Zard Recent progress in the generation and use of nitrogen-centred radicals. , 2008, Chemical Society reviews.

[45]  Zigang Li,et al.  Gold(III)-catalyzed nitrene insertion into aromatic and benzylic C-H groups. , 2007, Journal of the American Chemical Society.

[46]  Hiroshi Kageyama,et al.  Charge carrier transporting molecular materials and their applications in devices. , 2007, Chemical reviews.

[47]  J. Hartwig,et al.  Palladium-catalyzed coupling of ammonia and lithium amide with aryl halides. , 2006, Journal of the American Chemical Society.

[48]  M. M. Díaz‐Requejo,et al.  Cyclohexane and benzene amination by catalytic nitrene insertion into C-H bonds with the copper-homoscorpionate catalyst TpBr3CuNCMe. , 2003, Journal of the American Chemical Society.

[49]  F. Minisci Novel Applications of Free-Radical Reactions in Preparative Organic Chemistry , 2002 .

[50]  Michael P. Winters,et al.  New N- and O-arylations with phenylboronic acids and cupric acetate , 1998 .

[51]  Simon Saubern,et al.  New aryl/heteroaryl CN bond cross-coupling reactions via arylboronic acid/cupric acetate arylation , 1998 .

[52]  A. J. Blacker,et al.  Electrophilic amination of catecholboronate esters formed in the asymmetric hydroboration of vinylarenes , 1997 .

[53]  J. Hartwig,et al.  Palladium-catalyzed formation of carbon-nitrogen bonds. Reaction intermediates and catalyst improvements in the hetero cross-coupling of aryl halides and tin amides , 1994 .

[54]  S. Buchwald,et al.  Palladium-Catalyzed Aromatic Aminations with in situ Generated Aminostannanes , 1994 .

[55]  B. Trost,et al.  The atom economy--a search for synthetic efficiency. , 1991, Science.

[56]  F. Minisci,et al.  Polar effects in free radical reactions. Homolytic aromatic amination by the amino radical cation, •+NH3: reactivity and selectivity , 1984 .

[57]  Y. Chow,et al.  An investigation of the photodecomposition of N-bromosuccinimide; the generation and reactivity of succinimidyl radical , 1979 .

[58]  P. Skell,et al.  Addition reactions of imidyl radicals with olefins and arenes , 1978 .

[59]  Paul A Wender,et al.  Function-oriented synthesis, step economy, and drug design. , 2008, Accounts of chemical research.

[60]  M. Leclerc,et al.  Synthesis and Characterization of Polyaniline Derivatives: Poly(2-alkoxyanilines) and Poly(2,5-dialkoxyanilines) , 1995 .

[61]  P. Kovacic,et al.  Aromatic Amination with Hydroxylamine-O-sulfonic Acid1 , 1961 .