27208-38-4Relevant articles and documents
Kinetics and mechanism of hydrolysis of N-amidomethylsulfonamides
Iley, Jim,Lopes, Francisca,Moreira, Rui
, p. 749 - 753 (2001)
The kinetics of the hydrolyses of secondary and tertiary N-amidomethylsulfonamides were studied at 50 °C. Both types of N-amidomethylsulfonamide hydrolyse through acid- and base-catalysed processes, as indicated by the pH-rate profiles. The order of reactivity for the acid-catalysed pathway implies a mechanism involving protonation of the amide followed by expulsion of a neutral amide and formation of a sulfonyliminium ion. In the base-catalysed region, compound 5c, which is substituted at both amide and sulfonamide nitrogen atoms, hydrolyses by nucleophilic attack of hydroxide ion at the amide carbonyl carbon atom to form benzoic acid and a sulfonamide. In contrast, compound 5b, which contains a sulfonamide NH group, hydrolyses to benzamide and sulfonamide products by an E1cbrev mechanism involving ionisation of the sulfonamide. Compound 5a, which contains an amide NH, also hydrolyses to sulfonamide and amide products, probably by an E2 mechanism.
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Amin,de Mayo
, p. 1585,1587 (1963)
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Liler,Kosanovic
, p. 1084,1086,1088,1090 (1958)
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Synthesis, structure, redox behavior, catalytic activity and DFT study of a new family of ruthenium(III)1-(arylazo)naphtholate complexes
Ramesh, Madhan,Kalidass, Mani,Jaccob, Madhavan,Kaleeswaran, Dhananjayan,Venkatachalam, Galmari
, p. 33 - 41 (2017)
Treatment of [RuCl2(DMSO)4] with 1-(arylazo)naphthol ligands in benzene under reflux afford the air-stable new ruthenium(III) complexes with general composition [Ru(L-R)3] (L = bidentate O, N donor; R = H, CH3, OCH3, Br, NO2) in good yield. The 1-(arylazo)naphthol ligands behave as tris-bidentate O, N donors via naphtholic proton and azo nitrogen. The molecular and electronic structure of the complexes have been established by elemental analysis and spectral (FT-IR, UV–vis & EPR) methods. DFT calculations were also carried out on the complexes 1 and 3 along with X-ray crystallized geometry of complex 5. These complexes in dichloromethane solution show intense ligand-to-metal charge transfer (LMCT) transitions in the visible region. The absorption and g-tensor value of these complexes (1, 3 & 5) were also computed and compared along with the available experimental results. The redox behavior of the complexes has been investigated by cyclic voltammetry and the potentials are observed with respect to the electronic nature of substituents (R) in the 1-(arylazo)naphthol ligands. These complexes have shown great promise as catalysts for the conversion of aldehydes to primary amides in good yield.
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Pascual Vila,Granados
, p. 248,263, 264 (1944)
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A simple Ru catalyst for the conversion of aldehydes or oximes to primary amides
Hull, Jonathan F.,Hilton, Sheena T.,Crabtree, Robert H.
, p. 1243 - 1245 (2010)
Ru(DMSO)4Cl2 is catalytically active for converting aldehydes to primary amides via oxime intermediates. This catalyst is readily available, and requires no additional ligands, a great simplification compared to previous work. A Ru(II)/(IV) mechanism is proposed.
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Chattaway,Baxter
, p. 1987 (1913)
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Ugelstad,de Jonge
, p. 919,935, 937 (1957)
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Hoffenberg,Hauser
, p. 1496,1498 (1955)
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Decomposition of N′-benzoyl-N-nitrosoureas in aqueous media
Faustino, Celia,Garcia-Rio, Luis,Leis, Jose Ramon,Norberto, Fatima
, p. 154 - 161 (2005)
The decomposition of N′-benzoyl-N-methyl-N-nitrosourea (BMNU) in aqueous media over the 0-14 pH range has been studied. In basic and neutral media (6 a = 7.8) and subsequent decomposition of the conjugate base of the thus formed nitrosourea, via an intermediate benzoyl isocyanate. Support for this mechanism is provided by the presence of N,N′-dibenzoylurea in the final reaction mixtures, as the result of the trapping of benzoyl isocyanate with benzamide generated from hydrolysis of the former. The hydrolysis of BMNU takes place through three competitive pathways: spontaneous decomposition of the conjugate base of BMNU, and buffer-catalyzed and hydroxide ion catalyzed water addition to the carbonyl group of the deprotonated nitrosourea. N′-Benzoyl-N,N′-dimethyl-N-nitrosourea (BDMNU), a benzoyl nitrosourea lacking the acidic proton of BMNU, is hydrolyzed in basic media by attack of hydroxide ion on the carbonyl group of the urea. In acid media (0 pH 6), BMNU gives only deamination products, differing from the reported behavior of other N-nitroso compounds and of the isoster nitrosoguanidine, in which denitrosation is almost quantitative. The reaction is acid-catalyzed in the 0-2.5 pH range and pH-independent in the 3-5 pH range. The presence of general acid catalysis (a = 0.60), the absence of nucleophilic catalysis, and the thermodynamic activation parameters for the reaction support the mechanism proposed in the literature for the deamination of N-nitrosoureas in acidic media. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
Iodide Reduction of Sulfilimines. 3. Evidence of a Minor Role for Catalysis by Hydrogen Bonding in the Decomposition of Sulfurane Intermediates
Young, Paul R.,Huang, H. C.
, p. 1810 - 1813 (1987)
The iodide reduction of N-(substituted benzoyl or benzenesulfonyl)-S,S-dimethylsulfilimine ylides (aqueous solution, 25 deg C, μ = 1.0 with KCl) is first order with respect to iodide concentration in the pH range 0.5-5; the order with respect to the proton is slightly > 1.0.The solvent deuterium isotope effect for the reduction of N-(4-chlorobenzoyl)-S,S-dimethylsulfilimine ylide is kH/kD = 0.6.Electron-withdrawing groups in the leaving group accelerate the rate of the reaction and give βl.g. value of -0.67.General acid catalysis is observed in the reduction reaction with Broensted α values of 0.15 and 0.29 for 4-methoxybenzamide and 4-chlorobenzenesulfonamide leaving groups, respectively.The value of βl.g. increases with decreasing strength of the catalyzing acid and the term pxy = (δβl.g./δpKaHA) = (δα/δpKal.g.) ca. +0.05.The solvent deuterium isotope effect on the general catalyzed reduction reaction is small (kBH/kBD = 1.32) and independent of acid strength.For the solvent-catalyzed reaction, it is suggested that the rate-limiting step involves diffusion apart of the amide anion-iodosulfonium cation pair.It is concluded, however, that the observed general catalysis does not arise from hydrogen bonding effects in a preassociation-type mechanism, but rather it involves proton transfer that is concerted with S-N bond cleavage.
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Bender,Ginger
, p. 348,349 (1955)
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Stereochemistry of the Peptide α-Amidation Reaction involving Two Enzymes, Peptidylglycine α-Hydroxylating Monooxygenase (PHM) and Peptidylhydroxyglycine N-C Lyase (PHL)
Kawahara, Takashi,Suzuki, Kenji,Iwasaki, Yasuno,Shimoi, Hiroko,Akita, Munetaka,et al.
, p. 625 - 626 (1992)
Peptidylglycine α-hydroxylating monooxygenase (PHM), the first enzyme involved in the peptide α-amidation, has been shown to convert N-benzoylglycine, a model substrate, stereoselectively to S-N-benzoyl-α-hydroxyglycine, whereas peptidylhydroxyglycine N-C lyase (PHL), the second enzyme, has been found to react exclusively with S-form of the intermediate.
Benzaldoxime to benzamide rearrangement catalysed by rhodium(III) hydroxocomplexes: The influence of polynuclear species
Berdyugin, Semen,Volchek, Victoria,Asanova, Tatyana,Kolesov, Boris,Gerasimov, Evgeny,Filatov, Evgeny,Vasilchenko, Danila,Korenev, Sergey
, (2019)
Rhodium(III) hydroxide was shown previously to possess the catalytic activity in the rearrangement reaction of primary oximes to amides. Alkaline solutions of rhodium(III) chlorocomplexes are routinely used for Rh(OH)3 preparation and allow for a diversity of rhodium hydroxocomplexes that hold a wide range of catalytic properties. In this study, two Al2O3 supported catalysts containing 1) exclusively [Rh(OH)6]3? species and 2) a mixture of rhodium hydroxocomplexes with one to four rhodium atoms ([Rh(OH)6]3–, [Rh2(μ?OH)2(OH)8]4–, [Rh3(μ?OH)3(OH)12]6–, [Rh4(μ?OH)6(OH)12]6) were prepared, characterised (XRD, Raman, EXAFS) and tested in the benzaldoxime to benzamide rearrangement. The catalyst containing polynuclear complexes possessed at least three times higher turnover frequency (TOF) and better selectivity than the [Rh(OH)6]3– based catalyst. According to the EXAFS data, the reduction of rhodium(III) took place under reaction conditions yielding small rhodium clusters (CNRh-Rh = 4), which were proposed to be the active sites of catalysts.
AMINE-BORANES AS BIFUNCTIONAL REAGENTS FOR DIRECT AMIDATION OF CARBOXYLIC ACIDS
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Paragraph 0008-0009; 0063-0064, (2022/03/04)
The present invention generally relates to a process for selective and direct activation and subsequent amidation of aliphatic and aromatic carboxylic acids to afford an amide R3CONR1R2. That the process is capable of delivering gaseous or low-boiling point amines provides a major advantage over existing methodologies, which involves an intermediate of triacyloxyborane-amine complex [(R3CO2)3—B—NHR1R2]. This procedure readily produces primary, secondary, and tertiary amides, and is compatible with the chirality of the acid and amine involved. The preparation of known pharmaceutical molecules and intermediates has also been demonstrated.
Visible light-mediated synthesis of amides from carboxylic acids and amine-boranes
Chen, Xuenian,Kang, Jia-Xin,Ma, Yan-Na,Miao, Yu-Qi
supporting information, p. 3595 - 3599 (2021/06/06)
Here, a photocatalytic deoxygenative amidation protocol using readily available amine-boranes and carboxylic acids is described. This approach features mild conditions, moderate-to-good yields, easy scale-up, and up to 62 examples of functionalized amides with diverse substituents. The synthetic robustness of this method was also demonstrated by its application in the late-stage functionalization of several pharmaceutical molecules.
