Solid dispersions synthesis

SYNTHESIS To a vigorously stirred suspension of 18.6 g of 5-bromobourbonal in 100 mLCRjClj there was added 14.2 g methyl iodide, l.Ogdecyltriethylammonium iodide, and 120 mL 5% NaOH. The color was a deep amber, and within 1 min the top phase set up to a solid. This was largely dispersed with the addition of another 50 mL of water. The reaction was allowed to stir for 2 days. The lower phase was washed with H20, and saved. The upper phase was treated with another 100 mL CH2C12, 50 mL of 25% NaOH, another g of decyltriethylammonium iodide, and an additional 50 mL of methyl iodide. The formed solids dispersed by themselves in a few h to produce two relatively clear layers. Stirring was continued for an additional 3 days. The lower phase was separated, washed with H20, and combined with the earlier extract. The solvent was removed under vacuum to give 20.3 g of an amber oil that was distilled at 120-133 °C at 0.4 mm/Hg to yield 15.6 g of 3-bromo-4-methoxy-... 

Recent literature contains a multitude of examples of synthetic organic methodologies which have been optimized and applied to the solid-phase synthesis of combinatorial libraries [2]. In fact, the production of a number of these libraries has been realized on such systems as the Multipin SPOC [8], the DIVERSOMER [9] and the OntoBLOCK [10], All three apparatuses allow the automated production of spatially dispersed combinatorial libraries and facilitate the isolation, identification, screening and archiving of single compounds in distinct physical locations which are crucial factors during lead discovery and optimization. 

Using the Multipin SPOC systems, researchers at Chiron have demonstrated the automated solid-phase synthesis of peptoids 1 (Scheme 1) [12], while Ellman and co-workers have completed the synthesis of a combinatorial library of 11 200 spatially dispersed benzodiazepines 2 (Scheme 2) [13],... 

Sodium alginate, 40, 122 Sodium polyacrylate, 122,130 Sodium polysulfide, 64 Solid-phase synthesis, 32 Solids, 17,19,134 Solution spinning, 171 Solutions and dispersions, 117-131. See also Fluids... 

Sol-gel processing describes a type of solid materials synthesis procedure, performed in a liquid and at low temperature (typically T< 100 °C). The development of sol-gel techniques has long been known for preparations of metal oxides and has been described many times [30-38, 40-46, 65]. The process is typically used to prepare metal oxides via the hydrolysis of reactive precursors, usually alkoxides in an alcoholic solution, resulting in the corresponding hydroxide. It is usually easy to maintain such hydroxide in a dispersed state in the solvent. Condensation of the hydroxide molecules with loss of water leads to the formation of a network When hydroxide species undergo polymerization by condensation of the hydroxy... 

OPCM route of ceria—zirconia solid solutions synthesis appears to be reasonably flexible approach allowing to make rather broad substitution in cation and anion sublattices of fluorite-like oxides without appearance of new phases provided homogeneous mixing of starting salts is ensured. Reasonably high dispersion of samples thus obtained and disordered bulk and surface structure makes them promising candidates as catalysts and supports for red-ox reactions. 

The same group also reported a disperse system consisting of N-oxyl-immobilized polyethylene particles as disperse phase and aqueous NaHC03-NaBr as disperse medium [19]. N-Oxyl-immobilized poly(p-phenylenebenzobisthiazolc) network polymer particles (PBZTNT-N-oxyl) have also been developed. The polymer is effective for the anodic oxidation of alcohols to afford the corresponding ketones, aldehydes, and/ or carboxylic adds [20]. These achievements nicely demonstrate the potential of liquid-solid disperse systems for eledroorganic synthesis. 

Cellulose beads are spherical particles with diameters in the micrometer to millimeter scale, which are used in chromatography, solid-supported synthesis, protein immobilization, drug release, and so forth. In principle, bead production can be simplified into two procedures dropping and dispersion. Gericke has reported a method of preparing beads by dropping... 

The primary particle size of PVF obtained from synthesis decreases as the amount of halogen-free surfactant increases in the aqneous medinm. This is believed to occur because the number of micelles formed by the halogen-free surfactant increases with concentration, providing more nucleation sites for vinyl fluoride polymer particles. This increase in nucleation sites results in smaller particles that are colloidally more stable. As a result, higher solids dispersions can be prepared. ... 

Aerosol flame synthesis is a mature technology. A solid phase is generated by dispersing the metal precursors in a flame. The first reports are dated from the 1970s to the 1980s [17-19]. Reviews can be found in [20, 21]. Three different approaches are identified, depending on the state of precursor ... 

Yu, K.M.K., Steele, A.M., Zhu, J Fu, Q.J. and Tsang, S.C. (2003) Synthesis of well-dispersed nanoparticles within porous solid structures using surface-tethered surfactants in supercritical CO2-Journal of Materials Chemistry, 13 (1), 130-134. 

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