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LiFePnormalO4 was prepared using a melt casting technique of normalLi2CnormalO3 and FePnormalO4 precursors at 1000°C . The product was characterized by X-ray diffraction and is of the olivine structure with a minor amount of normalLi4normalP2normalO7 impurity. The synthesis, based on a molten procedure, provides a route to large-scale synthetic practices and reduced cost through the use of inexpensive precursors and short reaction times. The large particle sizes of the LiFePnormalO4 crystals obtained from the melt casting were reduced to 200nm by a series of successive milling techniques without affecting the purity of the sample. A subsequent carbon coating on this milled material with a variety of carbon precursors was capable of producing samples with high capacities and electrochemical results similar to that of commercial LiFePnormalO4 powders. These results indicate that the melt casting procedure could be a competitive synthetic technique for the large-scale production of LiFePnormalO4 .

A new, efficient and easy route for the preparation of a series of 2-alkyl(aryl) substituted 4-oxo-4H-pyrido-[1,2-a]pyrimidines, where alkyl = CH 3 ; aryl = C 6 H 5 , 4-FC 6 H 4 , 4-ClC 6 H 4 , 4-BrC 6 H 4 , 4-CH 3 C 6 H 4 , 4-OCH 3 -C 6 H 4 , 4-NO 2 C 6 H 4 in 45 -80 % yield from the reaction of β-alkoxyvinyl trichloromethyl ketones with 2-aminopyridine under mild conditions, is then reported.J. Heterocyclic Chem., 43, 229 (2006).In the last years, the introduction of a trifluoro-or trichloromethyl group into an acyclic or cyclic compound have widely been studied and reviewed [1,2]. Consequently, these new organic structures can bring about remarkable changes in their physical, chemical and biological properties.Recently, we have also reported an addition/elimination sequence leading to trifluoroacetyl and trichloroacetyl acyclic enamines from the reaction of o-phenylenediamine [3], o-aminophenol [4], 1-naphthylamine [5] and S,Sdimethylsulfoximide [6] with 4-alkyl(aryl)-1,1,1-trihalo-4-alkoxyalken-2-ones. The acyclic enaminones, derived from o-phenylenediamine and o-aminophenol, were submitted to in vitro anti-tumor screens. It was observed that the trichloromethylated compounds exhibited a superior activity if compared to trifluoromethylated analog compounds. The best activity was obtained when the structure was derived from o-aminophenol and it presents a trichloroacetyl-and a p-bromophenyl substituent bound at the carbon-2 and -1, respectively [4].β-Alkoxyvinyl trichloromethyl ketones 1 proved also to be useful building blocks for the synthesis of five-, six-, and seven-, member trichloromethylated heterocycles [2] due to the fact that one of the best methods to introduce a trichloromethyl group into heterocycles is based on the trichloromethylated building block approach. This approach relies on the trichloroacetylation of enol ethers or acetals to give, in one step and good yields, the above cited ketones 1. On the other hand, the classical haloform reaction in which the trichloromethyl substituent is a leaving group is well developed [7] and systematic studies, involving the usefulness of the leaving group ability of the trichloromethyl in many synthetic transformations, were reported [2,[8][9][10][11][12][13][14]. However, just a few references from the literature report the use of the trichloromethyl substituent as a good leaving group in heterocyclic synthesis [15]. Furthermore, the synthetic strategy involving the ketones 1 and 2-aminopyridine was never applied in attempt to obtain regiospecificaly 2-alkyl(aryl)substituted 4H-pyrido[1,2-a]pyrimidin-4-ones under relative mild conditions.Although some researches, up to 1951, considered that the heterocycle obtained from the reaction of 2-aminopyridine with ethyl acetoacetate was 4-methyl-2H-pyrido[1,2-a]pyrimidin-2-one, Antaki and Petrow [16] showed (in 1951), that the product was, in fact, the 2-methyl-4-keto isomer. To prove this hypothesis, 2-methyl-4H-pyrido[1,2-a]pyrimidin-4-one was obtained from the reaction of 2-bromopyridine with ethyl β-amin...

Magnetomigration of rare-earth ions activated by thermal and evaporation-based gradients was demonstrated with the help of Mach-Zehnder interferometry. Magnetic susceptibility gradients were induced in aqueous solutions of rare-earth ions by local heating/cooling or by evaporation of the solvent. Both methods yielded the enrichment of strongly paramagnetic Dy 3+ ions in the region of the highest magnetic field. Three different orientations of the magnetic field were tested using temperature as the source of magnetic susceptibility gradient. Enhanced magnetomigration was observed when gradients of magnetic field and magnetic susceptibility were non-collinear, indicating that the rotational component of the magnetic force drives the process. Additionally, four rare-earth ions with distinct values of magnetic susceptibility were studied: the diamagnetic ion Y 3+ , and the paramagnetic ions Nd 3+ , Gd 3+ and Dy 3+. A strong correlation between the obtained magnetomigration and the magnetic susceptibility of the rare-earth ions was found. When heating/cooling or evaporation were stopped during magnetization experiments, the magnetic effect gradually faded. This demonstrates that the presence of magnetic susceptibility gradients in the system is crucial for the magnetomigration. These findings are of importance for the development of a magnetic separation process for rare-earth ions.