Catalytic Oxidation of Primary C–H Bonds in Alkanes with Bioinspired Catalysts

Catalytic oxidation of primary C–H bonds of alkanes with a series of iron and manganese catalysts is investigated. Products resulting from oxidation of methylenic sites are observed when hexane (S1) is used as model substrate, while corresponding primary C–H bonds remain unreactive. However, by using 2,2,3,3-tetramethylbutane (S2) as model substrate, which only contains primary alkyl C–H bonds, oxidation takes place catalytically using a combination of hydrogen peroxide, a manganese catalyst and acetic acid as co-catalyst, albeit with modest yields (up to 4.4 TON). Complexes bearing tetradentate aminopyridine ligands provide the best yields, while a related pentadentate ligand provides smaller product yields. The chemoselectivity of the reaction is solvent dependent. Carboxylic acid 2b is observed as major product when the reaction takes place in acetonitrile, because of the facile overoxidation of the first formed alcohol product 2a. Instead the corresponding primary alcohol 2a becomes dominant in reactions performed in 2,2,2-trifluoroethanol (TFE). Polarity reversal of the hydroxyl moiety arising from the strong hydrogen bond donor ability of the latter solvent accounts for the unusual product chemoselectivity of the reaction. The significance of the current results in the context of light alkane oxidation is discussed.

Light Design and Textiles

Innovation textile is a new and unusual product type combining information technologies with wide art opportunities. The article considers three types of innovation textiles selected using the functional purpose principle: materials radiating light (electrofluorescence, light emitting diodes, including organic and fibre optics), materials forming an image (LC screens, OLED, LCD) and materials with fluorescence effect. A new cloth type named electronic textiles is a material, which conducts and at the same time consumes electric energy. It combined three formerly independent spheres: textiles, electrical engineering and electronic engineering. Textile materials are the base, on which various electronic devices are mounted.

Unusual product formation in a 1,1-carboboration reaction

The reaction of the cross-conjugated enediyne Me2CC(CCSiMe3)2with B(C6F5)3gives the unusual borabicyclo[4.3.0]nonadiene product.