Efficient Synthesis of 2-Arylamino-2-imidazolines and 2-Ami-nobenzimidazoles with Aminoiminomethanesulfonic Acid Derivatives

A highly efficient synthesis of 2‐arylamino‐2‐imidazolines and 2‐aminobenzimidazoles from aminoimino‐methanesulfonic acid derivatives is described. The method is simple and practical, generating imidazoline and benzimidazoline derivatives in excellent isolated yields.     

Sodium Borohydride – Ammonium Carbonate: An Effective Reducing System for Aldehydes and Ketones

Summary. Reduction of aldehydes and ketones to the corresponding alcohols was achieved in a simple procedure using the system sodium borohydride and ammonium carbonate. This system needs lower excesses of reducing agent and leads to significantly shortened reaction times.     

Synthesis and application of modified silica sulfuric acid as a solid acid heterogeneous catalyst in Michael addition reactions

Modified silica sulfuric acid (MSSA) as a new type of silica sulfuric acid was prepared and effectively used in the conjugate addition of indole, pyrrole, and thiols with Michael acceptors under mild conditions at room temperature. Also, MSSA was used as a catalyst for the synthesis of 1,1,3‐tri‐indolyl compounds in good to excellent yield at room temperature. J. Heterocyclic Chem., (2011).     

Tungstate supported mesoporous silica SBA‐15 with imidazolium framework as a hybrid nanocatalyst for selective oxidation of sulfides in the presence of hydrogen peroxide

In this work, a new heterogeneous catalyst (SBA‐15/Im/WO₄^2?) was prepared, and then its performance in the oxidation of organic sulfides was studied (using 30% H₂O₂ as green oxidant under neutral reaction conditions). This organic–inorganic hybrid mesoporous material was characterized by various techniques, such as FT‐IR, inductively coupled plasma, X‐ray powder diffraction, high‐resolution‐transmission electron microscopy, N₂ adsorption–desorption and thermogravimetric analysis. The catalyst was also applied to the selective oxidation of various sulfides. The hybrid catalyst was easily recovered, and was very stable and retained good activity for at least five successive runs without any additional activation. Moreover, there was no remarkable decrease in the activity and selectivity of the catalyst. The products could be easily isolated by just removing the solvent after filtering the catalyst. The yields of the catalytic productions through this catalyst were in the range from 75% to 97%.     

Ionic Liquids as Reagent and Reaction Medium: Preparation of Alkyl Aryl Ethers

Summary. Room temperature ionic liquid, [bmIm]OH, is used as a green recyclable reaction medium and reagent for the alkylation of phenols in excellent yields. The recovered ionic liquid was reused five to six times with consistent activity.     

N-Methylpiperidinium Chlorochromate Adsorbed on Alumina: A New Deoximation Reagent

 N-Methylpiperidinium chlorochromate adsorbed on alumina was found to be an efficient and selective reagent for the mild oxidative cleavage of oximes.     

N-Methylpiperidinium Chlorochromate Adsorbed on Alumina: A New Deoximation Reagent

Summary.  N-Methylpiperidinium chlorochromate adsorbed on alumina was found to be an efficient and selective reagent for the mild oxidative cleavage of oximes. Received March 1, 2001. Accepted March 22, 2001     

HIO4/Al2O3 as a new system for iodination of activated aromatics and 1,3-dicarbonyl compounds

The use of a periodic acid/alumina system for the iodination of activated aromatics and 1,3-dicarbonyl compounds is described.     

2-Hydroxy-N,N,N-tributylethanaminium thiocyanate as solvent and reagent for the preparation of alkyl thiocyanates

2-Hydroxy-N,N,N-tributylethanaminium thiocyanate was utilized as both solvent and reagent for the conversion of alkyl halides to the corresponding alkyl thiocyanates in good yields under mild conditions.     

Application of polymer-bound thiazolium salts to the synthesis of acyloins and benzoins: Effects of solvent and substituents of the thiazolium nucleus

Covalent immobilization of the thiazole nucleus on a chloromethylated polystyrene copolymer results in the formation of a catalytically active thiazolium salt, capable of repeated acyloin and benzoin condensations. The nature of the solvent and the substituents on the thiazolium nucleus has been found to have marked effects of the rate of catalysis.