104385-10-6Relevant academic research and scientific papers
3,3'-(Phenylphosphinylidene)bis and 3,3'-(Phenylphosphinylidene)bis. New Activating Agents
Ueda, Mitsuru,Mochizuki, Amane,Hiratsuka, Ichiro,Oikawa, Hideaki
, p. 3291 - 3297 (1985)
New activating agents, 3,3'-(phenylphophinylidene)bis (4) and 3,3'-(phenylphosphinylidene)bis (5), were readily prepared by the reaction of phenylphosphonic dichloride (3) with 2(3H)-benzoxazolone (1) and 2(3H)-benzothiazolone (2) respectively in the presence of triethylamine at room temperature.The new activating agents 4 and 5 were found to be useful for the preparation of amides, esters, and dipeptides under mild conditions.Furthemore, the direct polycondensation of isophthalic acid with aromatic diamines using the activating agent 4 in the presence of pyridine proceeded fast at room temperature to produce polyamides with inherent viscosities up to 0.80 dL/g.
Radical-Mediated Activation of Esters with a Copper/Selectfluor System: Synthesis of Bulky Amides and Peptides
Matsumoto, Akira,Wang, Zhe,Maruoka, Keiji
, p. 5401 - 5411 (2021/04/12)
Herein, we describe a new approach for the activation of esters via a radical-mediated process enabled by a copper/Selectfluor system. A variety of para-methoxybenzyl esters derived from bulky carboxylic acids and amino acids can be easily converted into the corresponding acyl fluorides, directly used in the one-pot synthesis of amides and peptides. As a proof of concept, this method was applied to the iterative formation of sterically hindered amide bonds.
Efficient cleavage of tertiary amide bonds: Via radical-polar crossover using a copper(ii) bromide/Selectfluor hybrid system
Maruoka, Keiji,Matsumoto, Akira,Wang, Zhe
, p. 12323 - 12328 (2020/12/08)
A novel approach for the efficient cleavage of the amide bonds in tertiary amides is reported. Based on the selective radical abstraction of a benzylic hydrogen atom by a CuBr2/Selectfluor hybrid system followed by a selective cleavage of an N-C bond, an acyl fluoride intermediate is formed. This intermediate may then be derivatized in a one-pot fashion. The reaction proceeds under mild conditions and exhibits a broad substrate scope with respect to the tertiary amide moiety as well as to nitrogen, oxygen, and carbon nucleophiles for the subsequent derivatization. Mechanistic studies suggest that the present reaction proceeds via a radical-polar crossover process that involves benzylic carbon radicals generated by the selective radical abstraction of a benzylic hydrogen atom by the CuBr2/Selectfluor hybrid system. Furthermore, a synthetic application of this method for the selective cleavage of peptides is described. This journal is
Synthesis of Secondary Amides from Thiocarbamates
Mampuys, Pieter,Ruijter, Eelco,Orru, Romano V. A.,Maes, Bert U. W.
supporting information, p. 4235 - 4239 (2018/07/29)
The synthesis of secondary amides from readily accessible and bench-stable substituted S-phenyl thiocarbamates and Grignard reactants is reported. Oxidative workup allows recycling of the thiolate leaving group as diphenyl disulfide. Diphenyl disulfide can be transformed into S-phenyl benzenethiosulfonate, a reactant required for thiocarbamate synthesis. This amide synthesis is suitable for the preparation of challenging amides that are not or hardly accessible via classical approaches.
A Practical and General Amidation Method from Isocyanates Enabled by Flow Technology
Williams, Jason D.,Kerr, William J.,Leach, Stuart G.,Lindsay, David M.
supporting information, p. 12126 - 12130 (2018/09/11)
The addition of carbon nucleophiles to isocyanates represents a conceptually flexible and efficient approach to the preparation of amides. This general synthetic strategy has, however, been relatively underutilized owing to narrow substrate tolerance and the requirement for less favourable reaction conditions. Herein, we disclose a high-yielding, mass-efficient, and scalable method with appreciable functional group tolerance for the formation of amides by reaction of Grignard reagents with isocyanates. Through the application of flow chemistry and the use of substoichiometric amounts of CuBr2, this process has been developed to encompass a broad range of substrates, including reactants found to be incompatible with previously published procedures.
Sulfur–Fluoride Exchange (SuFEx)-Mediated Synthesis of Sterically Hindered and Electron-Deficient Secondary and Tertiary Amides via Acyl Fluoride Intermediates
Smedley, Christopher J.,Barrow, Andrew S.,Spiteri, Christian,Giel, Marie-Claire,Sharma, Pallavi,Moses, John E.
supporting information, p. 9990 - 9995 (2017/08/01)
Amide bond formation is one of the most executed reactions in chemistry and biology. This is largely due to the ubiquity of the amide functional group in biological molecules, natural products and pharmaceutically important drugs. We report here the development of “SuFExAmide”: a new sulfur–fluoride exchange (SuFEx) click chemistry based protocol for the efficient amidation of carboxylic acids via acyl fluoride intermediates. We have developed benzene-1,3-disulfonyl fluoride as a cost effective, powerful and versatile coupling agent, which delivers challenging secondary and tertiary amides in excellent yields from sterically hindered and electron-deficient amines. The straightforward method offers significant benefits over existing protocols in terms of substrate scope, efficiency and ease of operation and is demonstrated by the synthesis of 44 amides, including GNF6702, an antiprotozoal drug candidate. In the majority of cases, the amide products are obtained in high yield without the need for excess reagents or chromatographic purification.
Method for catalyzing amidation reactions
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Page/Page column 13, (2008/06/13)
The invention provides a method of preparing a compound of formula 2 wherein R1 and R6 are as defined herein, by a catalytic amidation process in the presence of added carbon dioxide. The inventive methods show surprising rate enhancement relative to the corresponding uncatalyzed reaction.
Reactivity of diacyloxyiodobenzenes toward trivalent phosphorus nucleophiles
Makowiec, Slawomir,Rachon, Janusz
, p. 352 - 359 (2007/10/03)
The reaction of diacyloxyiodobenzenes and tetravalent phosphorus nucleophiles was investigated. It was established that both H-phosphonates and secondary phosphine oxides react with diacetoxyiodobenzene in alcohols in the presence of sodium alcoholates yi
