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Solvent free reactions

Reactions of nitrophenols in 8-hydroxyquinoline–benzoic acid eutectic melt

Journal of Thermal Analysis and Calorimetry
Authors: Preeti Gupta, Tanvi Agrawal, S. S. Das, and N. B. Singh

ionic liquids, supercritical carbon dioxide and water or to perform the reactions in solvent free conditions [ 6 – 9 ]. Keeping in mind the ease of preparation and ecofriendly conditions, attempts have been made to prepare some compounds through organic

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ethylenesulfide (Es) molecule in the polysaccharide chain through the reaction of the available amino group. An environmentally friendly solvent-free reaction was explored and the activity in sorbing divalent lead and cadmium from aqueous solution was studied

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Abstract  

Keggin heteropolyacids are found to be selective and recyclable catalysts for the preparation of flavones. The reaction was carried out in different reaction media, homogeneous, heterogeneous and solvent-free conditions. The solvent-free conditions represent the best green conditions.

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Andrés Pena, Santiago Veiga, Mariángeles Sapelli, Natalia Martínez, Victoria Márquez, Eduardo Dellacassa, and Juan Bussi

, although solvent-free conditions were also tested in some cases. When oxygen is used as the oxidant, an autooxidation mechanism is proposed to take place, in which the epoxidation and allylic oxidation products takes place by a free radical chain mechanism

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Abstract  

Cellulose was chemically modified with SOCl2 to obtain chlorodeoxycellulose, followed by a reaction that gave bonded ethylene-1,2-diamine (en), producing 6-(2′-aminoethylamino)-6-deoxycellulose. The reactions were carried out without the presence of solvent, in water or in N,N′-dimethylformamide, in which the highest amount of amino compound was incorporated onto the biopolymer backbone. The X-ray diffraction patterns for the chlorodeoxycellulose indicate new crystallinities that result from hydrogen bonds established through bonded chorine atoms and the remaining hydroxyl groups, while all the aminodeoxycelluloses were amorphous compounds. Thermal stabilities, for all aminated celluloses gave lower final mass losses than for the chlorinated biopolymer, whose value is lower than unmodified cellulose.

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(PW 12 O 40 ) as well as undecatungstophosphate (PW 11 O 39 ) for solvent free liquid phase oxidation of styrene using hydrogen peroxide as an oxidant. The oxidation reaction was studied by varying different parameters such as reaction time and amount

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(allyl glycidyl ether or 2-[(prop-2-en-1-yloxy)methyl] oxirane) is shown in Scheme 1 . The MPR[amim][X] catalyst was weighed in air (0.5 g) and introduced into a 55-mL high-pressure reactor containing 40 mmol of AGE under solvent-free conditions, and

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from green coffee beans ( Upadhyay et al., 2012 ), pesticides and metals. In this work the solvent free microwave extraction technique ( Lucchesi et al., 2004 ), as an alternative to the traditional ones, has been analyzed, based on microwave heating

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Mechanical mixing of molecular crystals

A green route to co-crystals and coordination networks

Journal of Thermal Analysis and Calorimetry
Authors: D. Braga, S. Giaffreda, M. Curzi, Lucia Maini, M. Polito, and Fabrizia Grepioni

Abstract  

Supramolecular reactions between crystalline materials can be exploited to prepare both hydrogen bonded co-crystals and coordination networks. Mechanical mixing of molecular crystals as well as kneading provide an alternative, solvent-free, route to novel materials hence these methods represent a green route to supramolecular solid-state chemistry.

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Abstract  

Three phenylenediammonium sulfate (PDAS) salts were prepared under solvent free conditions and characterized by gravimetric, spectroscopic and elemental analyses. Thermal decomposition studies of the salts have been investigated using TG (static air), TG/DTG and DSC (inert atmosphere). The thermal decomposition pathways have also been suggested and it has been found that PDAS salts on heating under vacuum in solid state give diaminobenzene sulfonic acids (DABSA) via proton transfer.

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