Hypervalent Iodine Catalyzed Hofmann Rearrangement of Carboxamides Using Oxone as Terminal Oxidant

2012 ◽  
Vol 77 (24) ◽  
pp. 11399-11404 ◽  
Author(s):  
Akira Yoshimura ◽  
Kyle R. Middleton ◽  
Matthew W. Luedtke ◽  
Chenjie Zhu ◽  
Viktor V. Zhdankin
Keyword(s):  
Hypervalent Iodine ◽  
Hofmann Rearrangement

Hypervalent iodine reagent-mediated reactions involving rearrangement processes

2020 ◽  
Vol 56 (91) ◽  
pp. 14119-14136
Author(s):  
Beibei Zhang ◽  
Xiaoxian Li ◽  
Boying Guo ◽  
Yunfei Du
Keyword(s):  
Claisen Rearrangement ◽  
Beckmann Rearrangement ◽  
Hypervalent Iodine ◽  
Ring Contraction ◽  
Hofmann Rearrangement ◽  
Rearrangement Processes

We summarize the developments of hypervalent iodine reagents-mediated reactions involving [1,2]-migration, Hofmann rearrangement, Beckmann rearrangement, ring contraction/expansion, [3,3]-sigmatropic/iodonium-Claisen rearrangement and some miscellaneous rearrangements.

Hofmann Rearrangement of Carboxamides Mediated by Hypervalent Iodine Species Generated in Situ from Iodobenzene and Oxone: Reaction Scope and Limitations

2010 ◽  
Vol 12 (20) ◽  
pp. 4644-4647 ◽  
Author(s):  
Aleksandra A. Zagulyaeva ◽  
Christopher T. Banek ◽  
Mekhman S. Yusubov ◽  
Viktor V. Zhdankin
Keyword(s):  
Hypervalent Iodine ◽  
Hofmann Rearrangement ◽  
Iodine Species

Asparagine-selective cleavage of peptide bonds through hypervalent iodine-mediated Hofmann rearrangement in neutral aqueous solution

2014 ◽  
Vol 5 (7) ◽  
pp. 2747 ◽  
Author(s):  
Kana Tanabe ◽  
Atsuhiko Taniguchi ◽  
Takuya Matsumoto ◽  
Kounosuke Oisaki ◽  
Youhei Sohma ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Hypervalent Iodine ◽  
Peptide Bonds ◽  
Hofmann Rearrangement ◽  
Neutral Aqueous Solution

Functional Group Interconversion

2015 ◽  
Author(s):  
Tristan H. Lambert
Keyword(s):  
Lone Pair ◽  
Hypervalent Iodine ◽  
Hofmann Rearrangement ◽  
Nitrogen Lone Pair ◽  
University Of Bristol ◽  
The University ◽  
Peptide Acids ◽  
Photochemical Cleavage ◽  
Sterically Induced ◽  
Direct Amidation

Chaozhong Li of the Shanghai Institute of Organic Chemistry reported (J. Am. Chem. Soc. 2012, 134, 10401) the silver nitrate catalyzed decarboxylative fluorination of carboxylic acids, which shows interesting chemoselectivity in substrates such as 1. A related decarboxylative chlorination was also reported by Li (J. Am. Chem. Soc. 2012, 134, 4258). Masahito Ochiai at the University of Tokushima has developed (Chem. Commun. 2012, 48, 982) an iodobenzene-catalyzed Hofmann rearrangement (e.g., 3 to 4) that proceeds via hypervalent iodine intermediates. The dehydrating agent T3P (propylphosphonic anhydride), an increasingly popular reagent for acylation chemistry, has been used (Tetrahedron Lett. 2012, 53, 1406) by Vommina Sureshbabu at Bangalore University to convert amino or peptide acids such as 5 to the corresponding thioacids with sodium sulfide. Jianqing Li and co-workers at Bristol-Myers Squibb have shown (Org. Lett. 2012, 14, 214) that trimethylaluminum, which has long been known to effect the direct amidation of esters, can also achieve the direct coupling of acids and amines, such as in the preparation of amide 8. The propensity of severely hindered 2,2,6,6-tetramethylpiperidine (TMP) amides such as 9 to undergo solvolysis at room temperature has been shown (Angew. Chem. Int. Ed. 2012, 51, 548) by Guy Lloyd-Jones and Kevin Booker-Milburn at the University of Bristol. The reaction proceeds by way of the ketene and is enabled by sterically induced destabilization of the usual conformation that allows conjugation of the nitrogen lone pair with the carbonyl. Matthias Beller at Universität Rostock has found (Angew. Chem. Int. Ed. 2012, 51, 3905) that primary amides may be transamidated via copper(II) catalysis. The conditions are mild enough that an epimerization-prone amide such as 11 undergoes no observable racemization during conversion to amide 13. A photochemical transamidation has been achieved (Chem. Sci. 2012, 3, 405) by Christian Bochet at the University of Fribourg that utilizes 385-nm light to activate a dinitroindoline amide in the presence of amines such as 15, which produces the amide 16. Notably, photochemical cleavage of the Ddz protecting group occurs at a shorter wavelength of 300 nm.

ChemInform Abstract: Hypervalent Iodine Catalyzed Hofmann Rearrangement of Carboxamides Using Oxone as Terminal Oxidant.

ChemInform ◽  
2013 ◽  
Vol 44 (19) ◽  
pp. no-no
Author(s):  
Akira Yoshimura ◽  
Kyle R. Middleton ◽  
Matthew W. Luedtke ◽  
Chenjie Zhu ◽  
Viktor V. Zhdankin
Keyword(s):  
Hypervalent Iodine ◽  
Hofmann Rearrangement

scholarly journals A Straightforward Synthesis of N-Substituted Ureas from Primary Amides

Synthesis ◽  
2020 ◽  
Vol 52 (14) ◽  
pp. 2099-2105
Author(s):  
Vincent Reboul ◽  
Nathalie Saraiva Rosa ◽  
Thomas Glachet ◽  
Quentin Ibert ◽  
Jean-François Lohier ◽  
...  
Keyword(s):  
Convenient Method ◽  
Nucleophilic Addition ◽  
Hypervalent Iodine ◽  
Hofmann Rearrangement ◽  
Ammonium Carbamate ◽  
Iodine Species ◽  
Ammonia Source

A direct and convenient method for the preparation of N-substituted ureas is achieved by treating primary amides with phenyliodine diacetate (PIDA) in the presence of an ammonia source (NH3 or ammonium carbamate) in MeOH. The use of 2,2,2-trifluoroethanol (TFE) as the solvent increases the electrophilicity of the hypervalent iodine species and allows the synthesis of electron-poor carboxamides. This transformation involves a nucleophilic addition of ammonia on the isocyanate intermediate generated in situ by a Hofmann rearrangement of the starting amide.

Recent Advances in the Hofmann Rearrangement and Its Application to Natural Product Synthesis

2020 ◽  
Vol 23 (22) ◽  
pp. 2402-2435
Author(s):  
Pradip Debnath
Keyword(s):  
Natural Products ◽  
Natural Product Synthesis ◽  
Biologically Active ◽  
Primary Amines ◽  
Hypervalent Iodine ◽  
Catalytic Systems ◽  
Waste Products ◽  
Factors Affecting ◽  
Hofmann Rearrangement ◽  
Recent Advances

: C-N bond formation reactions are the most important transformations in (bio)organic chemistry because of the widespread occurrence of amines in pharmaceuticals, natural products, and biologically active compounds. The Hofmann rearrangement is a well-known method used for the preparation of primary amines from amides. But, the traditional version of the Hofmann rearrangement often gave relatively poor yields due to over-oxidation or due to the poor solubility of some amides in aqueous base, and created an enormous amount of waste products. Developments over the last two decades, in particular, have focused on refining both of these factors affecting the reaction. This review covers both the description of recent advances (2000-2019) in the Hofmann rearrangements and its applications in the synthesis of heterocycles, natural products and complex molecules of biological interest. It is revealed that organo-catalytic systems especially hypervalent iodine-based catalysts have been developed for the green and environmentally friendly conversion of carboxamides to primary amines and carbamates.

ChemInform Abstract: Hofmann Rearrangement of Carboxamides Mediated by Hypervalent Iodine Species Generated in situ from Iodobenzene and Oxone: Reaction Scope and Limitations.

ChemInform ◽  
2011 ◽  
Vol 42 (7) ◽  
pp. no-no
Author(s):  
Aleksandra A. Zagulyaeva ◽  
Christopher T. Banek ◽  
Mekhman S. Yusubov ◽  
Viktor V. Zhdankin
Keyword(s):  
Hypervalent Iodine ◽  
Hofmann Rearrangement ◽  
Iodine Species

Oxidase Catalysis via an Aerobically Generated Dess-Martin Periodinane Analogue

2018 ◽  
Author(s):  
Asim Maity ◽  
Sung-Min Hyun ◽  
Alan Wortman ◽  
David Powers
Keyword(s):  
Chemical Synthesis ◽  
Aerobic Oxidation ◽  
Substrate Oxidation ◽  
Oxidation Catalysis ◽  
Hypervalent Iodine ◽  
Oxidation Reactions ◽  
Broad Array ◽  
Oxidation Chemistry ◽  
Reactive Oxidants

<p>Hypervalent iodine(V) reagents, such as Dess-Martin periodinane (DMP) and 2-iodoxybenzoic acid (IBX), are broadly useful oxidants in chemical synthesis. Development of strategies to access these reagents from O2 would immediately enable use of O2 as a terminal oxidant in a broad array of substrate oxidation reactions. Recently we disclosed the aerobic synthesis of I(III) reagents by intercepting reactive oxidants generated during aldehyde autoxidation. Here, we couple aerobic oxidation of iodobenzenes with disproportionation of the initially generated I(III) compounds to generate I(V) reagents. The aerobically generated I(V) reagents exhibit substrate oxidation chemistry analogous to that of DMP. Further, the developed aerobic generation of I(V) has enabled the first application of I(V) intermediates in aerobic oxidation catalysis.</p>

Regioselective C3-H Trifluoromethylation of 2H-Indazole Under Transition-Metal-Free Photoredox Catalysis

2019 ◽  
Author(s):  
Arumugavel Murugan ◽  
Venkata Nagarjuna Babu ◽  
Nagaraj Sabarinathan ◽  
Sharada Duddu. S
Keyword(s):  
Transition Metal ◽  
Visible Light ◽  
Practical Approach ◽  
Hypervalent Iodine ◽  
Radical Mechanism ◽  
Photoredox Catalysis ◽  
Metal Free

Here we report a visible-light-promoted metal-free regioselective C3-H trifluoromehtylation reaction that proceeds via radical mechanism and which supported by control experiments. The combination of photoredox catalysis and hypervalent iodine reagent provides a practical approach for the present trifluoromethylation reaction and synthesis of a library of trifluoromethylated indazoles.

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