Green and Fast Synthesis of 2-Arylidene-indan-1,3-diones Using a Task-Specific Ionic Liquid.

A novel method for condensation reaction of indan-1,3-dione with various aldehydes which are efficiently catalyzed by a task-specific ionic liquid, 2-hydroxyethylammonium formate, to provide the corresponding 2-arylidenindane-1,3-diones has been developed. This green, low-cost, high-yield, and fast reaction takes place at room temperature without the use of any solvent and catalyst. A plausible reaction mechanism that involves ionic liquid-assisted activation is also discussed. This work is the first report of ionic liquids as a reaction medium and catalyst for the synthesis of 2-arylidenindane-1,3-diones.

Biochemical and pharmacological characterization of isatin and its derivatives: from structure to activity.

Isatin, 1H-indole-2,3-dione, is a heterocyclic compound of significant importance in medicinal chemistry. It is a synthetically versatile molecule, a precursor for a large number of pharmacologically active compounds. Isatin and its derivatives have aroused great attention in recent years due to their wide variety of biological activities, relevant to application as insecticides and fungicides and in a broad range of drug therapies, including anticancer drugs, antibiotics and antidepressants. The purpose of this review is to provide an overview of the pharmacological activities of isatin and its synthetic and natural derivatives. Molecular modifications to tailor the properties of isatin and its derivatives are also discussed.

Ambiphilic dual activation role of a task-specific ionic liquid: 2-hydroxyethylammonium formate as a recyclable promoter and medium for the green synthesis of ß-nitrostyrenes.

A cost-effective task-specific ionic liquid, 2-hydroxyethylammonium formate, efficiently promotes the condensation of nitroalkanes with various aldehydes to produce ß-nitrostyrenes in high to excellent yields at room temperature. This reaction does not involve any hazardous organic solvent and toxic catalyst. The ionic liquid is recovered and recycled for subsequent reactions. In addition, a novel mechanism has been proposed invoking ambiphilic dual activation influence of the ionic liquid.

TAPC-promoted oxidation of sulfides and deoxygenation of sulfoxides.

1,3,5-Triazo-2,4,6-triphosphorine-2,2,4,4,6,6-tetrachloride (TAPC) was found to be an efficient promoter for the oxidation of sulfides and deoxygenation of sulfoxides. Excellent yields, short reaction time, easy and quick isolation of the products, solvent-free process, and excellent chemoselectivity are the main advantages of this procedure.

Direct conversion of thiols to sulfonyl chlorides and sulfonamides.

H(2)O(2) in combination with SOCl(2) proved to be a highly reactive reagent for the direct oxidative conversion of thiol derivatives to the corresponding sulfonyl chlorides with high purity through oxidative chlorination. Upon reaction with amines, the corresponding sulfonamides were obtained in excellent yields and in very short reaction times.

Polyfunctional tetrazolic thioethers through electrooxidative/Michael-type sequential reactions of 1,2- and 1,4-dihydroxybenzenes with 1-phenyl-5-mercaptotetrazole.

In the presence of 1-phenyl-5-mercaptotetrazole as a nucleophile, electrochemical oxidations of 1,2- and 1,4-dihydroxybenzenes have been investigated in aqueous solution using cyclic voltammetry and controlled-potential coulometry. The voltammetric results indicate that an electrooxidative/Michael-type sequential reaction occurs between the mercaptide anion and the electrochemically generated benzoquinones leading to the corresponding polyfunctional tetrazolic thioethers. The mechanism of electrochemical reaction is proved as an EC pathway using controlled-potential coulometry. In addition, the electrosyntheses of tetrazolic thioethers have been successfully performed in ambient conditions in an undivided cell using an environmentally friendly method with high atom economy.