Optically pure fullerodendron formed by diastereoselective Diels-Alder reaction

The Diels-Alder reaction between C₆₀ and anthryl glycodendron, which has d- or l-gluconamides at the terminals, gave a new fullerene glycodendron conjugate. Interestingly, the diastereoselective cycloaddition reaction proceeded upon the treatment of C₆₀ with the anthryl dendron 3. Furthermore, optical pure fullerodendrons (−)-4L and (+)-4D, which were confirmed by ¹H and ¹³C NMR spectroscopy, FT-IR, MALDI-TOF mass spectroscopic analysis, were isolated from the mixture of diastereomers. And their absolute configurations were predicted by the use of CD spectra.     

Blue-to-UVB Upconversion,Solvent Sensitization and Challenging Bond Activation Enabled by a Benzene-Based Annihilator

Several energy-demanding photoreactions require harsh UV light from inefficient light sources. The conversion of low-energy visible light to high-energy singlet states via triplet-triplet annihilation upconversion (TTA-UC) could offer a solution for driving such reactions under mild conditions. We present the first annihilator with an emission maximum in the UVB region that, combined with an organic sensitizer, is suitable for blue-to-UVB upconversion. The annihilator singlet was successfully employed as an energy donor in subsequent FRET activations of aliphatic carbonyls. This hitherto unreported UC-FRET reaction sequence was directly monitored using laser spectroscopy and applied to mechanistic irradiation experiments demonstrating the feasibility of Norrish chemistry. Our results provide clear evidence for a novel blue light-driven substrate or solvent activation strategy, which is important in the context of developing more sustainable light-to-chemical energy conversion systems.