Near-infrared monitoring of roller compacted ribbon density: Investigating sources of variation contributing to noisy spectral data.

The aim of this study was to highlight how variability in roller compacted ribbon quality can impact on NIR spectral measurement and to propose a simple method of data selection to remove erroneous spectra. The use of NIR spectroscopy for monitoring ribbon envelope density has been previously demonstrated, however to date there has been limited discussion as to how spectral data sets can contain erroneous outliers due to poor sample presentation to the NIR probes. In this study compacted ribbon of variable quality was produced from three separate blends of microcrystalline cellulose (MCC)/lactose/magnesium stearate at 8 Roll Force settings (2-16kN/cm).

Copper-catalyzed asymmetric oxidation of sulfides.

Copper-catalyzed asymmetric sulfoxidation of aryl benzyl and aryl alkyl sulfides, using aqueous hydrogen peroxide as the oxidant, has been investigated. A relationship between the steric effects of the sulfide substituents and the enantioselectivity of the oxidation has been observed, with up to 93% ee for 2-naphthylmethyl phenyl sulfoxide, in modest yield in this instance (up to 30%). The influence of variation of solvent and ligand structure was examined, and the optimized conditions were then used to oxidize a number of aryl alkyl and aryl benzyl sulfides, producing sulfoxides in excellent yields in most cases (up to 92%), and good enantiopurities in certain cases (up to 84% ee).