- A convenient Hofmann reaction of carboxamides and cyclic imides mediated by trihaloisocyanuric acids
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A simple, efficient and pot-economic approach in a single vessel has been developed for conversion of aromatic and aliphatic carboxamides into primary amines with one fewer carbom atom (Hofmann reaction) in 38–89 % yield by reacting with trichloro- or tribromoisocyanuric acid and sodium hydroxide in aqueous acetonitrile. Under the same reaction conditions, cyclic imides gave amino acids (69–83 %). The role of the trihaloisocyanuric acids is the in situ generation of N-haloamides, key-intermediates for the Hofmann reaction. The scalability of the methodology was demonstrated by a multigram-scale transformation of phthalimide into anthranilic acid in 77 % yield.
- Bastos, Gustavo A.,de Mattos, Marcio C.S.
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- Decarboxylative Amination: Diazirines as Single and Double Electrophilic Nitrogen Transfer Reagents
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The ubiquity of nitrogen-containing small molecules in medicine necessitates the continued search for improved methods for C-N bond formation. Electrophilic amination often requires a disparate toolkit of reagents whose selection depends on the specific structure and functionality of the substrate to be aminated. Further, many of these reagents are challenging to handle, engage in undesired side reactions, and function only within a narrow scope. Here we report the use of diazirines as practical reagents for the decarboxylative amination of simple and complex redox-active esters. The diaziridines thus produced are readily diversifiable to amines, hydrazines, and nitrogen-containing heterocycles in one step. The reaction has also been applied in fluorous phase synthesis with a perfluorinated diazirine.
- Chandrachud, Preeti P.,Wojtas, Lukasz,Lopchuk, Justin M.
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p. 21743 - 21750
(2021/01/11)
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- Carbon Dioxide as a Directing Group for C-H Functionalization Reactions Involving Lewis Basic Amines, Alcohols, Thiols, and Phosphines for the Synthesis of Compounds
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Methods of synthesizing compounds using CO2 as a directing group for C—H functionalization, and compounds made thereby, are described.
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Paragraph 0097-0099; 0109
(2019/07/03)
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- Carbon Dioxide-Mediated C(sp3)-H Arylation of Amine Substrates
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Elaborating amines via C-H functionalization has been an important area of research over the past decade but has generally relied on an added directing group or sterically hindered amine approach. Since free-amine-directed C(sp3)-H activation is still primarily limited to cyclization reactions and to improve the sustainability and reaction scope of amine-based C-H activation, we present a strategy using CO2 in the form of dry ice that facilitates intermolecular C-H arylation. This methodology has been used to enable an operationally simple procedure whereby 1° and 2° aliphatic amines can be arylated selectively at their γ-C-H positions. In addition to potentially serving as a directing group, CO2 has also been demonstrated to curtail the oxidation of sensitive amine substrates.
- Kapoor, Mohit,Liu, Daniel,Young, Michael C.
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supporting information
p. 6818 - 6822
(2018/05/31)
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- Preparation of secondary carbinamines via alkylation of N-boryl imines generated from partial reduction of nitriles with NABH4-carboxylic acid
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Secondary carbinamines have been prepared from alkylation of N-boryl imines which were generated in situ from partial reduction of nitriles with sodium borohydride modified by carboxylic acid.
- Itsuno,Hachisuka,Ushijima,Ito
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p. 3229 - 3234
(2007/10/02)
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- Preparation of Secondary Carbinamines via N-Boryl Imines Generated in situ from Nitriles and Borane-Tetrahydrofuran
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N-Boryl imines obtained from partial reduction of nitriles with borane-tetrahydrofuran have been alkylated with organolithium or Grignard reagents to afford secondary carbinamines in moderate to excellent yields.
- Itsuno, Shinichi,Hachisuka, Chiharu,Ito, Koichi
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p. 1767 - 1769
(2007/10/02)
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- Process for the production of amines
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Amines and substituted ureas are produced by reaction of carboxamides with hypochlorites in the presence of bromine, iodine, polymerization inhibitors, and/or haloamides and excess alkali metal hydroxide with or without the addition of primary or secondary amines. The products are perfumes and starting materials for the production of dyes, plant protection agents and perfumes.
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