Al2O3/MeSO3H (AMA) as a new reagent with high selective ability for monoesterification of diols

Surface passivation of carbon dots with ethylene glycol and their high-sensitivity to Fe3+

“…The mixture was stirred and heated at 80 C for 8 h. 22 Next, the solution was centrifuged at 16 000 rpm for 15 min to separate out the catalytic agents. Finally, the obtained H-CDs were dialyzed in water through a dialysis membrane (500 MWCO) for 72 h.…”

Synthesis, spectral studies and insect antifeedant activities of some 4-substituted 1-naphthacyl bromide and its esters

“…Green solventassisted and solvent-free reactions are useful for the synthesis of numerous organic compounds such as carbonyl compounds, pyrazolines and imines [10][11][12][13]. Among these reactions esterification and bromination reactions are important for the formation of carbon-bromine and carbon-oxygen bonds in carbonyl compounds [14,15]. Many natural organic compounds have methylene fragment in their structure and it is the origin for biological activity.…”

“…Many reagents like Copper(II)bromide [20], N,N-dimethylformamide [21], 1,4-dioxanebromooxoniumbromide [22], tribromoacetophenone [23], N-bromosaccharin [24], tribromoacetyl-tetrabutylammonium bromides [6], human esoinophils [25], peroxo-Mntetrabutylammoniumbromides [7,8], bromide-bromates [12], acylammonium salts-LDA quenches with bromine [26], benzylic bromides [27], pyridiniumbromide perbromide [28] and pyridinium bromochromate [29] have been utilized for the bromination of organic substrates. The reagents like Me 2 NSO 2 Cl and N,N-dimethylamines [30], (CH 3 O) 4 Sitetra-alkylorthosilicates in presence of Pd [31], t-BuOOC--CuBr [32], CO-CH 3 OH-i-PrNEt 2 with Pd [33], TFFH [34], dimethyl formamide-dipropylacetal or dimethylformamide-di-isopropylacetal with pyridine [14,15], 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methyl-morpholiniumchloride, N-methyl-2-bromo pyridinium iodide, N-methyl-2-chloropyridinium iodide and N-methyl-2-bromopyridinium tosylates [35], metal salt in liquid EDTA [36], Lewis acids and bases [37][38][39] have been employed for esterification of acids, acid chlorides, ethers, alcohols, halo alkanes, alkenes and salt derivatives. Herein the author reports an effective method for bromination selectively at the side chain in a 4-substituted 1-naphthyl ketones with potassium bromide-bromate mixture (Winkler's reagent) in the presence of fly-ash in water medium.…”

Synthesis of 2-substituted benzimidazoles and bis-benzimidazoles by microwave in the presence of alumina-methanesulfonic acid

“…We have previously reported that a mixture of AMA is an effective reagent for the conversion of alcohols into corresponding amides [11], Fries-rearrangement [12], Beckmann rearrangement [13], hydration of nitriles into amides [14], monoesterification of diols [15], N-nitrosation of secondary amines [16], and aromatization of 1,4-dihydropyridines [17]. In continuation of our work on the applications of AMA as a catalyst in organic reactions, herein we report the synthesis of benzimidazoles by the reaction of ortho-phenylenediamine and carboxylic acids in the presence of AMA under microwave irradiation.…”