Conducting polyaniline/cobaltous oxide composites have been synthesized using in situ deposition technique by placing fine graded/cobaltous oxide in polymerization mixture of aniline. The a.c. conductivity and dielectric properties are studied by sandwiching the pellets of these composites between the silver electrodes. It is observed that the values of conductivities increase up to 30 wt% of cobaltous oxide in polyaniline and decrease thereafter. Initial increment in conductivity is due to extended chain length of polyaniline where polarons possess sufficient energy to hop between favourable sites. Beyond 30 wt% of cobaltous oxide in polyaniline, blocking of charge carriers takes place reducing the conductivity values. It can be noted that the value of dielectric constant increases up to 10 wt% of cobaltous oxide. Thereafter, it decreases up to 30 wt% of cobaltous oxide and again increases up to 40 wt% of cobaltous oxide and decreases thereafter. The observed behaviour is attributed to the variation of a.c. conductivity. And it is observed that the dielectric loss increases up to 10 wt% of cobaltous oxide in polyaniline, decreases to a lower value of 20 wt% of cobaltous oxide and increases to 35 wt% and thereafter decreases. These values go in accordance with the values of dielectric constant. The results obtained for these composites are of greater scientific and technological importance.

Indium triflate catalyzes efficiently the one-pot threecomponent condensation of aldehydes, amines, and allyltributylstannane to afford the corresponding products of homoallylic amines in excellent yields at room temperature. All reactions were carried out using the catalyst in 10 mol%. This methodology was successfully applied to a variety of aldehydes and amines.The reaction in which three or more reactants come together in a single reaction vessel to form a new product that contain portions of all the components is called the multicomponent condensation reaction. The multicomponent condensation strategies offer significant advantages over conventional linear type synthesis to provide products with the diversity needed for the discovery of new lead compounds or lead optimization employing combinatorial chemistry. The one-pot synthesis of homoallylic amines comes under multicomponent condensation reactions in which aldehyde, amine, and allylating agent are reacting at a time. The resulting homoallylic amines are useful intermediates in the synthesis of biologically active compounds such as statin, conine, lobeline, sedamine, SKF-100330-A, epothilone, b-lactams, b-amino acids, and many natural products. 1 In view of the synthetic importance, the homoallylic amine preparation attracts many researchers. In general, homoallylic amines are prepared either by the addition of organometallic reagents to imines or by the nucleophilic addition of allylsilane or allyltin or allylborane or allylgermane reagents, in the presence of a variety of catalysts. 2 The catalysts include different metals such as magnesium, silicon, tin, samarium, lithium, zinc, cerium, boron, molecular iodine, indium and chromium, 3 metal halides such as CuI, TiCl 4 , SnCl 2 , TaCl 5 , 4 metal triflates, 5 ionic liquids, 6 metal perchlorates, BF 3 ·OEt 2 , metal oxychlorides, 7 and other catalysts. 8 However, many of the methods have some drawbacks, which involve use of strong Lewis acids, prolonged reaction times, vigorous reaction conditions, and low yields of products. Therefore, the development of an efficient one-pot synthesis of homoallylic amines is an active ongoing research area and there is scope for further improvement towards milder reaction conditions. Indium triflate is well known in the literature as an efficient catalyst for various organic transformations. 9 Herein we report a simple and efficient protocol for the synthesis of homoallylic amines using aldehyde, amine, and allyltributylstannane in the presence of a mild Lewis acid, indium triflate [In(OTf) 3 ], at room temperature.In a typical experiment, an equimolar amount of 3,4,5-trimethoxybenzaldehyde, p-toluidine, and allyltributylstannane were reacted in the presence of a catalytic amount (10% mol) of indium triflate to afford the corresponding derivative of 4-methyl-N-[1-(3,4,5-trimethoxyphenyl)but-3-enyl]benzeneamine (4a) as shown in Scheme 1. The conversion was complete within three hours at room temperature and the product was obtained in 95% yield (Table 1). In a similar m...

A simple and efficient route has been developed for the synthesis of anti-histamine drugs clocinizine and chlorcyclizine. The common intermediate 1-[(4-chloro phenyl) (phenyl)-methyl]-piperazine (8), is prepared from (4-chlorophenyl) (phenyl)-methanone (5), in three steps with excellent yields. All the reactions proceeded smoothly and the products were also isolated easily.

A Polymer Electrolyte Membrane (PEM) fuel cell is a device in which an electrochemical reaction occurs between fuel and oxidant producing electricity and water is the only by-product with zero emission. Usually, Pt nanoparticles prepared on carbon support used as oxidation and reduction reaction in PEM fuel cells. Because, carbon-supported platinum shows better oxidation and reduction activity among all the pure metals. Alloying of Pt with another non-noble metal is a strategy to develop Pt-based electrocatalysts, which reduces the Pt loading in electrodes and alters the intrinsic properties such as active sites available on surface and binding strength and electronic effect of species. Carbon support loss its catalytic activity due to electrooxidation under fuel cell operating conditions for long-term operations. In particular, the encapsulation of carbon with polyaniline (PANI) supported Pt enhances the electrode stability in fuel cells by Enhancing the Active Surface Area (EASA), chemical resistance and electron conductivity. Different supported catalysts have been proposed to improve electrochemical stability of nanoparticles in PEM fuel cells and supercapacitor.

A Simple and Efficient Method for the Three-Component Synthesis of Homoallylic Amines Catalyzed by Indium Triflate. -The process can be applied to a broad spectrum of substrates to give various title compounds as drug synthons. -(NARSAIAH*, A. V.; KUMAR, J. K.; NARSIMHA, P.; Synthesis