54616-47-6Relevant articles and documents
One-pot synthesis of a highly disperse core-shell CuO-alginate nanocomposite and the investigation of its antibacterial and catalytic properties
Habibi, Hassan,Mansourinejhad, Sanam,Saberi, Dariush,Shadi, Ahmad
, p. 199 - 211 (2021/12/30)
In this study, sodium alginate was extracted from Sargassum algae, collected from coastal waters of Bushehr, Persian Gulf, Iran and used as a stabilizing and wrapping agent for CuO nanoparticles. The synthesized nanocomposite was characterized by some spectroscopic and microscopic techniques, such as IR, XRD, Uv-vis, BET, BJH, zeta potential, SEM, TEM, HR-TEM, and XPS. The antibacterial effects of the CuO-alginate nanocomposite against some bacteria, isolated from a burn wound, were evaluated. The results showed that this nanocomposite had better antibacterial effects than its components onPseudomonas aeruginosaATCC 27853,Staphylococcus aureusATCC 12600,Streptococcus pyogenesATCC 19615, andStaphylococcus epidermidisATCC 49461. Among these,Staphylococcus aureusATCC 12600 was the most sensitive one to this nanocomposite, with the lowest minimum inhibitory concentration (2.08 mg mL?1) observed. Moreover, the synthesized nanocomposite showed good catalytic activity in the oxidative coupling of carboxylic acids withN,N-dialkylformamides toward the synthesis of amides.
Nickel-catalyzed regioselective C-H halogenation of electron-deficient arenes
Li, Ze-Lin,Wu, Peng-Yu,Cai, Chun
supporting information, p. 3462 - 3468 (2019/02/25)
A straightforward Ni(ii)-catalyzed general strategy was developed for the ortho-halogenation of electron-deficient arenes with easily available halogenating reagents N-halosuccinimides (NXS; X = Br, Cl and I). The transformation was highly regioselective and a wide substrate scope and functional group tolerance were observed. This discovery could be of great significance for the selective halogenation of amides, benzoic esters and other substances with guiding groups. Mechanistic investigations were also described.
Facile Access to Amides from Oxygenated or Unsaturated Organic Compounds by Metal Oxide Nanocatalysts Derived from Single-Source Molecular Precursors
Mohammad, Akbar,Chandra, Prakash,Ghosh, Topi,Carraro, Mauro,Mobin, Shaikh M.
, p. 10596 - 10608 (2017/09/12)
Oxidative amidation is a valuable process for the transformation of oxygenated organic compounds to valuable amides. However, the reaction is severely limited by the use of an expensive catalyst and limited substrate scope. To circumvent these limitations, designing a transition-metal-based nanocatalyst via more straightforward and economical methodology with superior catalytic performances with broad substrate scope is desirable. To resolve the aforementioned issues, we report a facile method for the synthesis of nanocatalysts NiO and CuO by the sol-gel-assisted thermal decomposition of complexes [Ni(hep-H)(H2O)4]SO4 (SSMP-1) and [Cu(μ-hep)(BA)]2 (SSMP-2) [hep-H = 2-(2-hydroxylethyl)pyridine; BA = benzoic acid] as single-source molecular precursors (SSMPs) for the oxidative amidation of benzyl alcohol, benzaldehyde, and BA by using N,N-dimethylformamide (DMF) as the solvent and as an amine source, in the presence of tert-butylhydroperoxide (TBHP) as the oxidant, at T = 80 °C. In addition to nanocatalysts NiO and CuO, our previously reported Co/CoO nanocatalyst (CoNC), derived from the complex [CoII(hep-H)(H2O)4]SO4 (A) as an SSMP, was also explored for the aforementioned reaction. Also, we have carefully investigated the difference in the catalytic performance of Co-, Ni-, and Cu-based nanoparticles synthesized from the SSMP for the conversion of various oxygenated and unsaturated organic compounds to their respective amides. Among all, CuO showed an optimum catalytic performance for the oxidative amidation of various oxygenated and unsaturated organic compounds with a broad reaction scope. Finally, CuO can be recovered unaltered and reused for several (six times) recycles without any loss in catalytic activity.
Oxidative amidation of benzaldehydes and benzylamines with: N -substituted formamides over a Co/Al hydrotalcite-derived catalyst
Gupta, Shyam Sunder R.,Nakhate, Akhil V.,Rasal, Kalidas B.,Deshmukh, Gunjan P.,Mannepalli, Lakshmi Kantam
, p. 15268 - 15276 (2017/12/15)
The present work describes a highly efficient synthetic strategy for amides via oxidative coupling of benzaldehydes or benzylamines with N-substituted formamides using a heterogeneous Co/Al hydrotalcite-derived catalyst in the presence of TBHP. A series of Co/Al hydrotalcite-derived catalysts (Cat-2, Cat-3, and Cat-4 with the Co2+/Al3+ molar ratio in the synthesis mixture as 1/1, 2/1 and 3/1) have been prepared by a simple co-precipitation method and characterized using powder XRD, XPS, FEG-SEM, EDS, FT-IR, DTG-TGA and N2 physical adsorption techniques. Among the as-prepared catalysts, Cat-3 exhibited excellent catalytic activity towards the direct amidation of benzaldehydes as well as benzylamines bearing various substituents into the corresponding amides at 100 °C using TBHP as an oxidant. The mechanistic investigation of the amidation reaction revealed that the reaction follows a radical pathway. Furthermore, the catalyst is easily separable and recyclable without considerable loss in catalytic activity.
Highly efficient preparation of amides from aminium carboxylates using N-(p-toluenesulfonyl) imidazole
Behrouz, Somayeh,Rad, Mohammad Navid Soltani,Forouhari, Elham
, p. 101 - 106 (2016/03/08)
Treatment of aminium carboxylates with N-(p-toluenesulfonyl)imidazole in the presence of triethylamine in DMF at 100 °C afforded the corresponding amides in good to excellent yields. N-(p-Toluenesulfonyl)imidazole proved to be a highly efficient coupling reagent for the preparation of numerous structurally diverse primary, secondary and tertiary amides.
Oxidative coupling of methylamine with an aminyl radical: Direct amidation catalyzed by I2/TBHP with HCl
Gao, Lingfeng,Tang, Haoming,Wang, Zhiyong
supporting information, p. 4085 - 4088 (2014/04/03)
Oxidative coupling of methylamines with an aminyl radical to construct amides was developed in the presence of an I2/TBHP catalyst under acidic conditions via the two cleavages of the sp3 C-N bond of aryl-methylamines and the sp2 C-N bond of N-substituted formamides respectively. This transition-metal-free protocol provides a novel synthetic tool for the construction of N-substituted amides and a series of arylamides can be easily obtained with good yields. This journal is the Partner Organisations 2014.
High-yielding, versatile, and practical [Rh(III)Cp*]-catalyzed ortho bromination and iodination of arenes
Schroeder, Nils,Wencel-Delord, Joanna,Glorius, Frank
, p. 8298 - 8301 (2012/06/29)
We report a uniquely high-yielding, general, and practical ortho bromination and iodination reaction of different classes of aromatic compounds. This reaction occurs by Rh(III)-catalyzed C-H bond activation methodology and is therefore the first example of the application of this cationic catalyst for C-Br and C-I bond formation.
Direct amidation of alcohols with N-substituted formamides under transition-metal-free conditions
Xu, Kun,Hu, Yanbin,Zhang, Sheng,Zha, Zhenggen,Wang, Zhiyong
supporting information; experimental part, p. 9793 - 9797 (2012/09/05)
Go tandem! The first example of the direct amidation of alcohols with N-substituted formamides has been developed. A series of tertiary amides, including the challenging N,N-dimethyl-substituted amides, were obtained in moderate to good yields under transition-metal-free conditions (see scheme). TBHP=tert-butyl hydroperoxide. Copyright
Investigation of the mechanism of C(sp3)-H bond cleavage in Pd(0)-catalyzed intramolecular alkane arylation adjacent to amides and sulfonamides
Rousseaux, Sophie,Gorelsky, Serge I.,Chung, Benjamin K. W.,Fagnou, Keith
supporting information; experimental part, p. 10692 - 10705 (2010/11/05)
The reactivity of C(sp3)-H bonds adjacent to a nitrogen atom can be tuned to allow intramolecular alkane arylation under Pd(0) catalysis. Diminishing the Lewis basicity of the nitrogen lone pair is crucial for this catalytic activity. A range of N-methylamides and sulfonamides react exclusively at primary C(sp3)-H bonds to afford the products of alkane arylation in good yields. The isolation of a Pd(II) reaction intermediate has enabled an evaluation of the reaction mechanism with a focus on the role of the bases in the C(sp3)-H bond cleaving step. The results of these stoichiometric studies, together with kinetic isotope effect experiments, provide rare experimental support for a concerted metalation-deprotonation (CMD) transition state, which has previously been proposed in alkane C(sp3)-H arylation. Moreover, DFT calculations have uncovered the additional role of the pivalate additive as a promoter of phosphine dissociation from the Pd(II) intermediate, enabling the CMD transition state. Finally, kinetic studies were performed, revealing the reaction rate expression and its relationship with the concentration of pivalate.
Carbanionic friedel-crafts equivalents. Regioselective directed Ortho and remote metalation-C-N cross coupling routes to acridones and dibenzo[b,f]azepinones
MacNeil, Stephen L.,Gray, Matthew,Gusev, Dmitry G.,Briggs, Laura E.,Snieckus, Victor
supporting information; experimental part, p. 9710 - 9719 (2009/04/07)
(Chemical Equation Presented) Carbanion-mediated general regioselective routes to acridones 4 (Table 2) and dibenzo[b,f]azepinones 20 (Table 4) are described. Buchwald-Hartwig C-N cross coupling of o-halo benzamides 1 with anilines 2 or 16, followed by simple N-methylation, dependably provides N-methyl diarylamines 3 (Table 1) and 18 (Table 3). Upon treatment with LDA, 3 and 18 are converted into acridones 4 and dibenzo[b,f]azepinones 20, respectively, in good to excellent yields with regioselectivity which depends upon the presence or absence of directed metalation groups (DMGs). Brief investigations as follows are described: the synthesis of desmethyl acridone 15 (Scheme 4), an attempt to effect a double-directed remote metalation sequence which leads only to a monocyclization product 13 (Scheme 3), and an analogous but nonregioselective route to a xanthone 22 and dibenzo[b,f]oxepinone 24 (Scheme 5). DFT calculations reveal low energy conformations for compounds 18b and 23 which account for product formation and indicate that the cyclization reactions are under kinetic control.
