The enantioselective reactions of lithiated benzyl trifluoromethyl sulfones with a substoichiometric amount of a bis(oxazoline) and various aldehydes is disclosed. The products were formed with excellent diastereo- and enantioselectivities. Fluorination of the sulfone with N-fluorobenzenesulfonimide and a stoichiometric amount of a bis(oxazoline) gave products with extremely high enantioselectivities (up to 99% ee; ee=enantiomeric excess). The enantioselective reaction was confirmed to proceed through a dynamic thermodynamic resolution pathway.

Making a resolution: The catalytic enantioselective reaction of lithiated benzyl trifluoromethyl sulfone with aldehydes delivers products with excellent diastereoselectivity as well as high enantioselectivity. Fluorination of the sulfone with N‐fluorobenzensulfonimide in the presence of a stoichiometric amount of bis(oxazoline)s resulted in extremely high enantioselectivity (up to 99 % ee, see scheme).

Chirale Sulfone: Die katalytischen Umsetzungen von lithiiertem Benzyltrifluormethylsulfon mit Aldehyden verlaufen mit ausgezeichneter Diastereoselektivität und hoher Enantioselektivität. Auch die Fluorierung des Sulfons mit N‐Fluorbenzolsulfonimid in Gegenwart stöchiometrischer Mengen an Bis(oxazolinen) war außerordentlich enantioselektiv (bis 99 % ee).

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Visible light is present everywhere in our lives. Widespread use of computers and smartphones has increased the daily time spent in front of screens. What effect does this visible light have on us? Recent studies have shown that short-wavelength blue light (400-450nm) irradiation, similar to UV, inhibits the cell proliferation and differentiation, induces the intracellular oxidative stress, promotes the cell apoptosis and causes some other negative effects. However, it’s unusual that directly face to such short-wavelength and high-energy blue light in daily life. Therefore, the effects of blue light with longer wavelength (470nm), lower energy (1, 2 J/cm2) and multiple times (simulated daily use) exposure on cells have been studied in this experiment. In our results, low energy density multiple blue light inhibited cell proliferation and metastatic capability with a weak phototoxicity. Blue light also promoted intracellular reactive oxygen species and caused DNA damage. Furthermore, the melanin synthesis was also promoted by low energy density multiple blue light exposure. Together, these results indicate that longer wavelength and low energy density blue light multiple exposure is still harmful to our cells. Furthermore, prolonged exposure to screens likely induces dull skin through induction of melanin synthesis. These results further mentioned us should paid more attention to controlling the daily use of digital device.