http://nopr.niscair.res.in/handle/123456789/6424 <b>Special Issue on Green/Sustainable Chemistry</b> Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/6702 Title: Microwave effect in organic reactions <br/> <br/>Authors: Dewan, Sharwan K <br/> <br/>Abstract: Based upon extensive analysis of the organic reactions reported in the literature, a qualitative method for the prediction of the presence or absence of specific microwave effect in organic reactions has been advanced. The specific microwave effect will be observed only if all the reactants are polar in nature. It is unlikely to be observed if the reactions involve a non-polar reactant. <br/> <br/>Page(s): 2337-2340 http://nopr.niscair.res.in/handle/123456789/6701 Title: An environmentally benign protocol for the synthesis of 3,4-dihydropyrimidin-2(1<i style="">H</i>)-ones using solid acid catalysts under solvent-free conditions <br/> <br/>Authors: Kumar, Dalip; Mishra, Braja Gopal; Rao, V S <br/> <br/>Abstract: Phosphotungstic acid/sulfated zirconia catalyzed one-pot condensation of aryl aldehydes, urea derivatives and β-diketones under microwave irradiation rapidly affords substituted 3,4-dihydropyrimidin-2(1<i style="">H</i>)-ones in excellent yields and high purity. The low cost catalysts have exhibited remarkable reactivity and reusability for the aforementioned synthesis. <br/> <br/>Page(s): 2325-2329 http://nopr.niscair.res.in/handle/123456789/6700 Title: Neat reaction technology: A green tool <br/> <br/>Authors: Kidwai, Mazaahir; Mothsra, Poonam <br/> <br/>Abstract: A solvent free approach for organic synthesis is described which involve microwave exposure of neat reactants. A variety of cyclization and condensation are carried out including the efficient one pot assembly of heterocyclic molecules from <i style="">in situ</i> generated intermediates. <br/> <br/>Page(s): 2330-2336 http://nopr.niscair.res.in/handle/123456789/6699 Title: Greener organic syntheses under non-traditional conditions <br/> <br/>Authors: Varma, Rajender S <br/> <br/>Abstract: A solvent-free approach that involves microwave (MW) exposure of neat reactants (undiluted) catalyzed by the surfaces of less-expensive and recyclable mineral supports such as alumina, silica, clay, or ‘doped’ surfaces is presented which is applicable to a wide range of cleavage, condensation, cyclization, rearrangement, oxidation and reduction reactions including rapid one-pot assembly of heterocyclic compounds from <i style="">in situ</i> generated reactive intermediates. The strategy is adaptable to multi-component reactions e.g. Ugi and Biginelli reactions for rapid assembly of a library of compounds. Synthesis of a wide variety of significant precursors and intermediates namely, enones, imines, enamines, nitroalkenes, and oxidized sulfur species is possible and their value in concise MW synthesis of 2-aroylbenzofurans, and thiazole derivatives is illustrated. Ultrasound- and MW-assisted solventless preparation of ionic liquids and their application in alkylation and metal-catalyzed multi-component reactions is described. Efficient reaction of epoxides with carbon dioxide provides ready access to cyclic carbonates using only a catalytic amount of recyclable indium-based ionic liquid. MW heating in aqueous reaction media enables expeditious <i style="">N</i>-alkylation reactions of amines and hydrazines to afford a series of heterocyclic ring systems such as <i style="">N</i>-azacycloalkanes, 4,5-dihydropyrazoles, pyrazolidines etc. <br/> <br/>Page(s): 2305-2312