Acetylated oligosaccharides are common in nature. While they are involved in several biochemical and biological processes, the role of the acetyl groups and the complexity of their migration has largely gone unnoticed. In this work, by combination of organic synthesis, NMR spectroscopy and quantum chemical modeling, we show that acetyl group migration is a much more complex phenomenon than previously known. By use of synthetic oligomannoside model compounds, we demonstrate, for the first time, that the migration of acetyl groups in oligosaccharides and polysaccharides may not be limited to transfer within a single monosaccharide moiety, but may also involve migration over a glycosidic bond between two different saccharide units. The observed phenomenon is not only interesting from the chemical point of view, but it also raises new questions about the potential biological role of acylated carbohydrates in nature.

Reductive amination of cyclohexanone with benzylamine was investigated at 100 °C under 30 bar hydrogen in toluene with five different gold catalysts prepared by deposition-precipitation method and supported on TiO 2 , La 2 O 3 /TiO 2 , CeO 2 / TiO 2 , La 2 O 3 and CeO 2. Size of metallic gold varied in the range of 2.6-3.6 nm. The best catalysts in reductive amination of cyclohexanone with benzylamine were 4 wt% Au/TiO 2 and 4 wt% Au/CeO 2 /TiO 2 giving 72% and 79% yield of the desired amine. The most acidic and basic catalysts were also unselective and exhibited low activity towards imine hydrogenation. The best catalyst 4 wt% Au/CeO 2 /TiO 2 gave in reductive amination of propiophenone 56% selectivity to the corresponding amine at 20% conversion in 5 h.

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Furfural oxidation with hydrogen peroxide was performed using sulfated zirconia as an acid catalyst within the temperature range of 40–90 °C. The catalytic behavior of sulfated zirconia due to its acidic character was different from a previously studied fibrous polymer-supported sulfonic acid catalyst Smopex-101. While maleic and succinic acids along with 2­(5-H)-furanone and formic acid were formed, selectivity to succinic acid was lower. Moreover, significant amounts of 5-hydroxy-2­(5-H)-furanone were generated as confirmed by nuclear magnetic resonance (NMR). In parallel to furfural oxidation giving products with four carbon atoms and formic acid, also furoic acid was formed and oxidized further. The reaction network proposed previously was modified and extended to account for these observations. In particular, the oxidation of 2­(5-H)-furanone to maleic acid, considered to be a plausible step over Smopex-101, turned out to be very slow in the presence of sulfated zirconia. The kinetic model developed on the basis of the reaction network was able to describe the concentration profiles of the reactants, intermediates, and products as a function of reaction time at different temperatures including decomposition of hydrogen peroxide.

An azide-functionalized 12-armed Buckminster fullerene has been monosubstituted in organic media with a substoichiometric amount of cyclooctyne-modified oligonucleotides. Exposing the intermediate products then to the same reaction (i.e., strain-promoted alkyne–azide cycloaddition, SPAAC) with an excess of slightly different oligonucleotide constituents in an aqueous medium yields molecularly defined monofunctionalized spherical nucleic acids (SNAs). This procedure offers a controlled synthesis scheme in which one oligonucleotide arm can be functionalized with labels or other conjugate groups (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid, DOTA, and Alexa-488 demonstrated), whereas the rest of the 11 arms can be left unmodified or modified by other conjugate groups in order to decorate the SNAs’ outer sphere. Extra attention has been paid to the homogeneity and authenticity of the C 60 -azide scaffold used for the assembly of full-armed SNAs.