Eutectic mixtures of urea and a range of quaternary ammonium salts are liquid at ambient temperatures and have interesting solvent properties.

A new system for NH transfer is developed for the preparation of sulfoximines, which are emerging as valuable motifs for drug discovery. The protocol employs readily available sources of nitrogen without the requirement for either preactivation or for metal catalysts. Mixing ammonium salts with diacetoxyiodobenzene directly converts sulfoxides into sulfoximines. This report describes the first ...

NH(4)(C(6)H(5))(4)B represents a prototypical system for understanding aromatic H bonds. In NH(4)(C(6)H(5))(4)B an ammonium cation is trapped in an aromatic cage of four phenyl rings and each phenyl ring serves as a hydrogen bond acceptor for the ammonium ion as donor. Here the dynamical properties of the aromatic hydrogen bond in NH(4)(C(6)H(5))(4)B were studied by quasielastic incoherent neut...

Chemically speciated concentrations of PM2.5 (sulphate, ammonium, nitrate, elemental and organic carbon) were simulated in south-west Europe using the three-dimensional air quality model CAMx driven by the MM5meteorological model. The inner domain covered the south-west region of Spain with a high spatial (2 km 2 km) and temporal resolution (1 h). The simulation results were evaluated against e...

In 1916 Jacobs, Heidelberger, and coworkers at the Rockefeller Institute reported the discovery of a new class of synthetic compounds which possessed potent bactelicidal properties. By reacting hexamethylenetetramine with a large variety of substituted benzylor alkyl-halides, nujmerous quaternary salts of this base were obtained. It was observed that most of these salts had pronounced bacterici...