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A Facile Procedure for the Conversion of Oximes to Ketones and Aldehydes with Potassium Dichromate in Dimethylformamide under Homogeneous Conditions

“…Therefore, there has been considerable interest in the development of mild techniques for this transformation. The most important procedure for the regeneration of their corresponding carbonyl compounds from the oxime is oxidative cleavage reaction, which has been accomplished by a variety of chromium (VI) based reagents, such as Jones reagent [4], methylammonium chlorochromate-Alumina [5], chromium trioxide-silica gel [6], pyridinium fluorochromate [7], quinolinium dichromate [8], potassium dichromate [9], pyridinium fluorochromatehydrogen peroxide [10], 2,6-dicarboxypyridinium chlorochromate [11], γ-picolinium chlorochromate [12], benzyltriphenylphosphonium chlorochromate [13], quinolinium fluorochromate [14], tetramethylammonium fluorochromate (VI) [15], benzyltrimethylammonium fluorochromate (VI) [16], imidazolium dichromate [17], dicarboxypyridinium fluorochromate [18], tetrabutylammonium chromate [19], chromic acid [20], chromium trioxide-NaHSO 4 H 2 O [21], glycinium chlorochromate-silica gel [22], ammonium chlorochromate-montmorillonite K10 [23], etc. Most of them are carried out under either heterogeneous conditions or solvent-free/solid state conditions.…”

Analysis of thermally-induced effects in Planck Low Frequency Instrument

“…To meet the cryogenic requirements a dedicated chain of cryo-coolers will be implemented on-board the Planck satellite. The 20 K stage, in common between the two instruments, will be provided by a Sorption Cooler [3], a vibration-less cryostat with a cooling capability of >1 W at 20 K. The heart of the cooler is composed by six hydride compressor beds in which hydrogen is alternatively absorbed and released as the temperature of the beds is modulated, thus creating a constant gas flow. The activity of such compressors generates second-order temperature oscillations that will propagate through the satellite and may affect the thermal boundaries between the spacecraft and the Planck instruments.…”