1204-55-3Relevant academic research and scientific papers
Biogenic CuFe2O4 magnetic nanoparticles as a green, reusable and excellent nanocatalyst for acetylation reactions under solvent-free conditions
Chutia, Rituparna,Chetia, Bolin
, p. 15200 - 15206 (2018/09/29)
A convenient green method has been developed for the synthesis of biogenic CuFe2O4 magnetic nanoparticles using tea extracts within a very short reaction time. The prepared nanoparticles with an average size of 8.78 nm have been used as an effective catalyst for the acetylation of various alcohols, phenols and amines in good to excellent yields under solvent-free conditions. The catalyst was characterized by XRD, XPS, VSM, SEM and TEM study. A magnetic study of the fresh and recycled catalyst after the fourth cycle was performed by VSM measurement. The main advantages of this protocol are simple biogenic synthesis of the catalyst, a reusable and heterogeneous catalytic system, and short reaction times with excellent yields.
Metal-free synthesis of benzothiazoles from disulfides of 2-aminobenzenethiol and carboxylic acid via PCl3-promoted tandem reaction
Du, Guangyan,Zhu, Ning,Han, Limin,Hong, Hailong,Suo, Quanling
, p. 1723 - 1734 (2015/12/12)
A metal-free process for the synthesis of benzothiazoles via PCl3-promoted cleavage/acylation/ cyclization of disulfides and carboxylic acids has been developed. In addition to acting as the acylating reagent which converted carboxylic acids into acyl chlorides, PCl3 also converted disulfides to thiols, which promoted disulfides of 2-aminobenzenethiol reacted with carboxylic acid to produce benzothiazoles. The developed method is applicable to a wide range of carboxylic acids containing different functional groups.
A novel silver nanoparticle embedded mesoporous polyaniline (mPANI/Ag) nanocomposite as a recyclable catalyst in the acylation of amines and alcohols under solvent free conditions
Mandi, Usha,Roy, Anupam Singha,Banerjee, Biplab,Islam, Sk. Manirul
, p. 42670 - 42681 (2015/02/19)
A mesoporous polyaniline/silver (mPANI/Ag) nanocomposite has been prepared using mesoporous organic polymer polyaniline with silver nitrate via radical polymerization of aniline monomer in the presence of hydrochloric acid. The mPANI/Ag nanocomposite has been characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray spectra (EDX), Fourier transform infrared spectroscopy (FT-IR), and ultraviolet-visible absorption spectra (UV-vis). The XRD patterns indicated that the crystalline phase of Ag is cubic. TEM images show that the Ag nanoparticles are well dispersed in the mesoporous polyaniline matrix. The mPANI/Ag acts as an efficient heterogeneous nanocatalyst in the acylation of substituted amines and alcohols using acetic acid. The catalyst is air-stable, inexpensive, easy to prepare and can be reused several times without a significant decrease in activity and selectivity. This journal is
Efficient Cu-catalyzed base-free C-S coupling under conventional and microwave heating. A simple access to S-heterocycles and sulfides
Soria-Castro, Silvia M.,Penenory, Alicia B.
, p. 467 - 475 (2013/05/08)
S-aryl thioacetates can be prepared by reaction of inexpensive potassium thioacetate with both electron-rich and electron-poor aryl iodides under a base-free copper/ligand catalytic system. CuI as copper source affords S-aryl thioacetates in good to excellent yields, by using 1,10-phenanthroline as a ligand in toluene at 100°C after 24 h. Under microwave irradiation the time was drastically reduced to 2 h. Both procedures are simple and involve a low-cost catalytic system. This methodology was also applied to the "one-pot" synthesis of target heterocycles, such as 3H-benzo[c][1,2]dithiol-3-one and 2-methylbenzothiazole, alkyl aryl sulfides, diaryl disulfides and asymmetric diaryl sulfides in good yields.
Amorphous carbon-silica composites bearing sulfonic acid as solid acid catalysts for the chemoselective protection of aldehydes as 1,1-diacetates and for N-, O- and S-acylations
Gupta, Princy,Paul, Satya
experimental part, p. 2365 - 2372 (2011/10/31)
Amorphous carbon-silica composites bearing sulfonic acid derived from inexpensive natural organic compounds (glucose, maltose, cellulose, chitosan and starch) were prepared by partial carbonization followed by sulfonation and their catalytic activity was evaluated for the protection of aldehydes as 1,1-diacetates and for N-, O- and S-acylations under solvent-free conditions. Different biomaterials have been chosen, with a view to select the most active solid acid catalyst. Carbon-silica composites were characterized by FTIR, XRD and elemental analysis. Sulfonated carbon-silica composite derived from starch was found to be the most active and could be recycled for several runs without loss of significant activity. It was also characterized by TGA, SEM and TEM.
A new odorless one-pot synthesis of thioesters and selenoesters promoted by Rongalite
Dan, Weixing,Deng, Hongjuan,Chen, Jiuxi,Liu, Miaochang,Ding, Jinchang,Wu, Huayue
experimental part, p. 7384 - 7388 (2010/10/02)
Rongalite promotes cleavage of diaryl disulfides generating chalcogenolate anions that then undergo facile acylation with anhydrides in the presence of CsF to afford thioesters (3) with good to excellent yields. By using the present protocol, 5-arylthio-5-oxopentanoic acid (4) can be facilely prepared. The important features of the methodology are broad substrate scope, simple operation, and no requirement for metal catalysts. It is noteworthy that acylations of diphenyl diselane with anhydrides are also conducted smoothly to afford selenoesters (5) in good yields under the standard conditions.
Additive-free chemoselective acylation of amines
Temperini, Andrea,Terlizzi, Raffaella,Testaferri, Lorenzo,Tiecco, Marcello
experimental part, p. 295 - 302 (2010/03/30)
Aliphatic and aromatic amines are efficiently acylated by acetic, pivalic, benzoic, phthalic, or maleic anhydrides in ethyl acetate at room temperature. Under the same experimental conditions, amino alcohols are chemoselectively acylated at the amino group.
Chemoselective acylation of amines in aqueous media
Naik, Sarala,Bhattacharjya, Gitalee,Talukdar, Bandana,Patel, Bhisma K.
, p. 1254 - 1260 (2007/10/03)
Amines are efficiently acylated by both cyclic and acyclic anhydrides by dissolving them in an aqueous medium with the help of a surfactant, sodium dodecyl sulfate (SDS). Cyclic and acyclic anhydrides react with equal ease with an amine, and amines with various stereo-electronic factors react at the same rates with an anhydride. Chemoselective acylation of amines in the presence of phenols and thiols and of thiols in the presence of phenols has been achieved. No acidic or basic reagents are used during the reaction. No Chromatographic separation is required for isolation of the acylated products. Reactions in a neutral aqueous medium, easy isolation of products, and innocuous by-products make the present method a green chemical process. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.
Ac2O-Py/basic alumina as a versatile reagent for acetylations in solvent-free conditions under microwave irradiation
Paul, Satya,Nanda, Puja,Gupta, Rajive,Loupy, André
, p. 4261 - 4265 (2007/10/03)
Acetic anhydride-pyridine over basic alumina has been used in order to carry out acetylations of hydroxy, thiol and amino groups in solvent-free conditions under microwave irradiation. The technique can be extended for selective acetylations by regulation of irradiation time.
