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The selection of electronically-different thiolate-based photosensitizers is employed to achieve a precise and specific C–F bond defluorination of a broad range of trifluoromethylarenes, enabling the synthesis of 88 α,α-difluoromethyl compounds. 

We report a metal-free strategy to access fluoroalkyl–olefin linkages from RCF₂H (R = aryl, H, F and fluoroalkyl) precursors and vinyl-pinacol boronic ester (BPin) reagents. 

Fluorine-containing allyl compounds are prevalent in drugs and bioactive molecules. Here, we report a straightforward and efficient radical pentafluorosulfanylation of allyl sulfones using sulfur chloride pentafluoride (SF₅Cl) to synthesize structurally diverse pentafluorosulfanyl allylic compounds. This transformation exhibits excellent functional group tolerance and achieves an impressive isolated yield of up to 98% in just 1 minute under ultraviolet light. Mechanistic studies suggest that the sulfonyl group acts as a free radical leaving group, with the capability of abstracting the chlorine atom from SF₅Cl. This radical chain propagation pathway facilitates the rapid regeneration of the sulfur pentafluoride radical, resulting in a notably high quantum yield. Moreover, this light-driven radical pentafluorosulfanylation simplifies the synthetic pathway to modify complex and bioactive molecules. In addition, the drug-modified pentafluorosulfanyl compounds exhibited promising effects in inhibiting cancer cell proliferation, both in vitro and in vivo. Therefore, this protocol provides a practical synthetic route to radical pentafluorosulfanylation, highlighting its potential in drug discovery. 

Abstract We outline a new synthetic method to prepare mono‐ and polyfluoroepoxides from a diverse pool of electrophiles (ketones, acyl chlorides, esters) and fluoroalkyl anion equivalents. The initially formed α‐fluoro alkoxides undergo subsequent intramolecular ring closure when heated. We demonstrated the versatility of the method through the isolation of 16 mono‐ and polyfluoroepoxide products. These compounds provide unique entry points for further diversification via either fluoride migration coupled with ring opening, or defluorinative functionalization reactions, the latter of which can be used as a late‐stage method to install select bioactive moieties. The reaction sequences described herein provide a pathway to functionalize the commonly observed products formed from 1,2‐addition into carbonyl electrophiles 

Bacterial suspensions—a premier example of active fluids—show an unusual response to shear stresses. Instead of increasing the viscosity of the suspending fluid, the emergent collective motions of swimming bacteria can turn a suspension into a superfluid with zero apparent viscosity. Although the existence of active superfluids has been demonstrated in bulk rheological measurements, the microscopic origin and dynamics of such an exotic phase have not been experimentally probed. Here, using high-speed confocal rheometry, we study the dynamics of concentrated bacterial suspensions under simple planar shear. We find that bacterial superfluids under shear exhibit unusual symmetric shear bands, defying the conventional wisdom on shear banding of complex fluids, where the formation of steady shear bands necessarily breaks the symmetry of unsheared samples. We propose a simple hydrodynamic model based on the local stress balance and the ergodic sampling of nonequilibrium shear configurations, which quantitatively describes the observed symmetric shear-banding structure. The model also successfully predicts various interesting features of swarming vortices in stationary bacterial suspensions. Our study provides insights into the physical properties of collective swarming in active fluids and illustrates their profound influences on transport processes.