Reactions of (η-RC5H4)Fe(CO)2I (R = H, Me) complexes with phosphine ligands PR′3 (R′ = Ph, m-Tol, p-C6H4OMe, p-C6H4Cl, p-C6H4F) have been performed under solvent-free conditions in the melt phase and generally yielded the ionic products [(η5-RC5H4)Fe(CO)2PR′3]I rather than the CO substituted products (η5-RC5H4)Fe(CO)(PR′3)I. The complexes have been characterised by IR, NMR and MS techniques. By...

a mild and efficient method has been developed for the preparation of substituted coumarins from reaction of various phenols with different β-ketoesters via pechmann condensation in the presence of brønsted acidic ionic liquid (n-(4-sulfonic acid) butyl triethylammonium hydrogen sulfate) as an effective catalyst under solvent-free conditions. different phenols reacted with ethyl acetoacetate to...

A irradiação de chalconas com microondas na ausência de solvente se mostrou um procedimento de “química verde” para a preparação, em bons rendimentos, de flavanonas. Diferentes catalisadores heterogêneos e catalisadores convencionais foram testados usando-se um forno de microondas doméstico. A irradiação de chalconas com 30% de ácido trifluoroacético, na presença de gel de sílica, levou a forma...

An efficient methodology was developed for performing palladium-catalyzed E-E (E = S, Se) bond addition to alkynes under solvent free conditions. Compared to reaction in solvent significant enhancement of reaction rate, improved efficiency and remarkable catalyst stability were observed under solvent free conditions. The addition reactions were carried out with high stereoselectivity and yields...

Daniel et al.1 demonstrated the effectiveness of dense bottlebrush polymers in lowering the entanglement density, that is, reducing the physical interaction level, by stiffening the main chains through the growth of numerous side chains—the bottlebrush structure. This breakthrough work is based on earlier works of the late Pakula.2 Sheiko’s group has been working on this topic for several years...

— An attempt is made to provide a more rigorous basis for the description of solvent effects on chemical reactions by taking into account the various free energy contributions involved in the transfer of a substrate from the gas to the solution phase. It is shown that the solvent influence on various chemical and physical processes can be represented in a semiquantitative or even quantitative w...

A practical and green method for the synthesis of 5H-dibenzo[b,i]xanthene-tetraones and spiro[dibenzo[b,i]xanthene-13,3'-indoline]-pentaones by the condensation of 2-hydroxynaphthalene-1,4-dione with aldehydes or isatins, respectively, in the presence of a catalytic amount of cellulose sulfuric acid (CSA) under solvent-free conditions at 100 °C is described. The significant features of this pro...

Oxalic acid dihydrate as a green, mild and efficient catalyst for the one-pot three-component Biginelli synthesis of 3,4-dihydropyrimidin-2-(1H)-one derivatives from the reaction between β-keto esters (methyl or ethyl acetoacetate), aromatic aldehyde (benzaldehye derivatives) and urea or thiourea under thermal and solvent-free conditions with excellent yields and short reaction time is st...