1119-49-9Relevant articles and documents
Cyclic guanidine organic catalysts: What is magic about triazabicyclodecene?
Kiesewetter, Matthew K.,Scholten, Marc D.,Kirn, Nicole,Weber, Ryan L.,Hedrick, James L.,Waymouth, Robert M.
, p. 9490 - 9496 (2009)
(Chemical Equation Presented) The bicyclic guanidine 1,5,7- triazabicyclo[4.4.0]dec-5-ene (TBD) is an effective organocatalyst for the formation of amides from esters and primary amines. Mechanistic and kinetic investigations support a nucleophilic mechanism where TBD reacts reversibly with esters to generate an acyl-TBD intermediate that acylates amines to generate the amides. Comparative investigations of the analogous bicyclic guanidine 1,4,6-triazabicyclo[3.3.0]oct-4-ene (TBO) reveal it to be a much less active acylation catalyst than TBD. Theoretical and mechanistic studies imply that the higher reactivity of TBD is a consequence of both its higher basicity and nucleophilicity than TBO as well as the high reactivity of the acyl-TBD intermediate, which is sterically prevented from adopting a planar amide structure.
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Hawkins,Tarbell
, p. 2982,2984 (1953)
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The Amidation of Carboxylic Acid with Amine over Hydrous Zirconium(IV) Oxide
Takahashi, Kyoko,Shibagaki, Makoto,Kuno, Hideyuki,Kawakami, Hiroshi,Matsushita, Hajime
, p. 1333 - 1334 (1989)
The reaction of a carboxylic acid or an ester with an amine to give the corresponding amide was carried out efficiently over hydrous zirconium(IV) oxide, whether in the vapor phase or in the liquid phase.
Kinetic Analysis of Ester Aminolysis Catalyzed by Nucleosides in a Nonpolar Medium. Evidence of Bifunctional Catalysis
Melander, Christian,Horne, David A.
, p. 9295 - 9297 (1997)
Kinetic analysis of ester aminolysis in benzene catalyzed by 2′,3′,5′-O-tris(tert-butyldimethylsilyl)-protected nucleosides and 2-pyridone is reported. The catalytic rate constant k3′ was determined for protected nucleosides A, C, G, U, and pseudouridine (Ψ). The relatively high value associated with C and 2-pyridone is indicative of bifunctional catalysis occurring through stabilization of the aminolysis transition state. The implications of this finding on the possible role C plays in biological catalysis during protein synthesis is hypothesized. ? Abstract published in Advance ACS Abstracts, December 1, 1997.
Ueki et al.
, p. 1108,1110 (1971)
Structure-reactivity correlation in the aminolysis of 4-fluorophenyl acetate in aqueous medium
Rajarathnam,Jeyakumar,Ananthakrishna Nadar
, p. 366 - 373 (2002)
The reaction of the title substrate with a series of amines of varying pKa, viz. ammonia, ethanolamine, glycine, 1,2-diaminopropane, 1,3-diaminopropane, n-butylamine, piperidine, hydrazine, imidazole, and hydroxylamine is subjected to a kinetic study in aqueous medium, 25°C, ionic strength 0.1 M (KCl). Pseudo-first-order rate coefficients (kobs) are found throughout under amine excess at various pH values for each amine. For amines, excluding hydrazine, ammonia, and hydroxylamine the reaction follows clean second-order kinetics and the plots of (kobs - kH) against free amine concentration are linear at constant pH. The macroscopic nucleophilic substitution rate coefficients (kN) are obtained as the slopes of these plots and found to be pH independent. For hydrazine, ammonia, and hydroxylamine, a rate dependence on more than first power of the amine is observed, accordingly, the rate constants for the assisted paths have been disseminated for these amines besides kN. The Broensted-type plot (logkN against amine pKa) is linear with a slope value of β = 1.02. The magnitude of the slope value is consistent with a stepwise mechanism through a zwitterionic tetrahedral addition intermediate whose breakdown to products is rate-determining (k2 step). A remarkable reactivity difference is observed among the diamines, the reason for which is discussed in detail.
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de Benneville et al.
, p. 1072,1075 (1956)
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A CO2-Catalyzed Transamidation Reaction
Yang, Yang,Liu, Jian,Kamounah, Fadhil S.,Ciancaleoni, Gianluca,Lee, Ji-Woong
, p. 16867 - 16881 (2021/11/18)
Transamidation reactions are often mediated by reactive substrates in the presence of overstoichiometric activating reagents and/or transition metal catalysts. Here we report the use of CO2as a traceless catalyst: in the presence of catalytic amounts of CO2, transamidation reactions were accelerated with primary, secondary, and tertiary amide donors. Various amine nucleophiles including amino acid derivatives were tolerated, showcasing the utility of transamidation in peptide modification and polymer degradation (e.g., Nylon-6,6). In particular,N,O-dimethylhydroxyl amides (Weinreb amides) displayed a distinct reactivity in the CO2-catalyzed transamidation versus a N2atmosphere. Comparative Hammett studies and kinetic analysis were conducted to elucidate the catalytic activation mechanism of molecular CO2, which was supported by DFT calculations. We attributed the positive effect of CO2in the transamidation reaction to the stabilization of tetrahedral intermediates by covalent binding to the electrophilic CO2
PRODUCTION METHOD OF AMIDE COMPOUND
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Paragraph 0018; 0089-0106, (2020/10/08)
PROBLEM TO BE SOLVED: To provide a production method of an amide compound, which can use a variety of carboxylic acid halides and can produce a desired amide compound at a yield higher than a batch process by suppressing a side reaction. SOLUTION: Provided is a production method of an amide compound using a flow type reactor, in which the flow type reactor includes: a first flow path; a second flow path; a first mixing means provided at a confluent part of the first flow path and the second flow path; and a third flow path that is connected to the first mixing means and arranged on a down stream side of the first mixing means, the production method comprising: a mixing step of obtaining a mixed liquid by circulating a first liquid containing the carboxylic acid halide in the first flow path, circulating a second liquid containing an amine compound having a molecular weight of 1,000 or less, an inorganic alkali and water in the second flow path, and mixing the first liquid and the second liquid by the first mixing means to obtain a mixture; and a reaction step of obtaining an amide compound by circulating the mixed liquid in the third flow path and reacting the carboxylic acid halide and the amine compound in the third flow path. SELECTED DRAWING: Figure 1 COPYRIGHT: (C)2020,JPO&INPIT
Direct synthesis of secondary amides from ketones through Beckmann rearrangement using O-(mesitylsulfonyl)hydroxylamine
Chandra, Dinesh,Verma, Saumya,Pandey, Chandra Bhan,Yadav, Ajay K.,Kumar, Puneet,Tiwari, Bhoopendra,Jat, Jawahar L.
supporting information, (2020/03/23)
The Beckmann rearrangement is a versatile method for the preparation of secondary amides from ketones via oxime intermediates and has been widely used in the synthesis of bioactive natural products and pharmaceuticals. Herein, we have developed a highly efficient direct method for the preparation of secondary amides and lactams from ketones using O-(mesitylsulfonyl)hydroxylamine (MSH). The reactions proceed rapidly at room temperature under mild condition without requiring any additive, and tolerate multiple functional groups. A simple aqueous work-up often furnished the products in excellent yield with high purity.
