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 https://www.lookchem.com/CASDataBase_4205-23-6.htm A highly selective self-condensation of glycolaldehyde to different C 4  molecules has been achieved using Lewis acidic stannosilicate catalysts in water at moderate temperatures (40–100 °C). The medium-sized zeolite pores (10-membered ring framework) in Sn-MFI facilitate the formation of tetrose sugars while hindering consecutive aldol reactions leading to hexose sugars. High yields of tetrose sugars (74 %) with minor amounts of vinyl glycolic acid (VGA), an α-hydroxyacid, are obtained using Sn-MFI with selectivities towards C 4  products reaching 97 %. Tin catalysts having large pores or no pore structure (Sn-Beta, Sn-MCM-41, Sn-SBA-15, tin chloride) led to lower selectivities for C 4  sugars due to formation of hexose sugars. In the case of Sn-Beta, VGA is the main product (30 %), illustrating differences in selectivity of the Sn sites in the different frameworks. Under optimized conditions, GA can undergo further conversion, leadi

 https://www.lookchem.com/CASDataBase_74111-21-0.htm (Chemical Equation Presented) Linear (n = 2-18) and cyclic oligomers (n = 3-8) of a cyclohexylether-δ-amino acid (COA) were prepared in high yield and stereopurity. CD spectra of the linear oligomers were indicative of secondary structure formation. X-ray crystal structures of cyclic COA oligomers revealed hydrophobic packing and internal 5- and 10-membered-ring hydrogen bonds. Ether and amide oxygens reside preferably in an ap orientation. This conformational locking is apparently broken by a C-2 substituent in an asymmetric cyclotrimer, for which a zeolithe-like tubular structure was found.

https://www.lookchem.com/CASDataBase_100-64-1.htm o -Iodoxybenzoic acid (IBX) is confirmed as a powerful tool for the oxidation of hydroxylamines. The synthetic route is demonstrated as efficient and user friendly, and is exploited on various carbohydrate-derived N,N-disubstituted hydroxylamines (cyclic, acyclic, and functionalized ones), affording the corresponding nitrones in good yields and regioselectivity. N-Monosubstituted hydroxylamines revealed an interesting divergent behavior depending on the reaction conditions. While IBX oxidation in dimethyl sulfoxide at 45 °C furnished oximes as reported, the oxidation in dichloromethane at room temperature afforded efficiently the unusual corresponding nitroso dimers. 

https://www.lookchem.com/CASDataBase_431-47-0.htm Immobilization of rhodium (palladium)-copper-chloride catalytic systems in ionic liquids as high-boiling-point solvents affects the distribution of propane oxidation products: the acetone yield increases and the yield of alcohols decreases. Propane is oxidized to acetone, bypassing the isopropanol formation step. Methane is oxidized under more severe conditions than propane, giving methyl trifluoroacetate as the main product. Mechanisms of action of the catalytic systems based on rhodium and palladium are close to each other and likely include oxo or peroxo complexes as intermediates.