Search for: All records

The development of efficient organic sonosensitizers is crucial for sonodynamic therapy (SDT) in the field of cancer treatment. Herein, a new strategy for the development of efficient organic sonosensitizers based on triarylboron‐doped acenethiophene scaffolds is presented. The attachment of boron to the linear acenethiophenes lowers the lowest unoccupied molecular orbital (LUMO) energy, resulting in redshifted absorptions and emissions. After encapsulation with the amphiphilic polymer DSPE‐mPEG₂₀₀₀, it is found that the nanostructured BAnTh‐NPs and BTeTh‐NPs (nanoparticles of BAnTh and BTeTh) shows efficient hydroxyl radical (^•OH) generation under ultrasound (US) irradiation in aqueous solution with almost no phototoxicity, which can overcome the shortcomings of O₂‐dependent SDT and avoid the potential cutaneous phototoxicity issue. In vitro and in vivo therapeutic results validate that boron‐doped acenethiophenes as sonosensitizers enable high SDT efficiency with low phototoxicity and good biocompatibility, indicating that boron‐functionalization of acenes is a promising strategy toward organic sonosensitizers for SDT.

Ultralong afterglow emissions due to room‐temperature phosphorescence (RTP) are of paramount importance in the advancement of smart sensors, bioimaging and light‐emitting devices. We herein present an efficient approach to achieve rarely accessible phosphorescence of heavy atom‐free organoboranes via photochemical switching of sterically tunable fluorescent Lewis pairs (LPs). LPs are widely applied in and well‐known for their outstanding performance in catalysis and supramolecular soft materials but have not thus far been exploited to develop photo‐responsive RTP materials. The intramolecular LPM1BNMnot only shows a dynamic response to thermal treatment due to reversible N→B coordination but crystals ofM1BNMalso undergo rapid photochromic switching. As a result, unusual emission switching from short‐lived fluorescence to long‐lived phosphorescence (rad‐M1BNM,τ_RTP=232 ms) is observed. The reported discoveries in the field of Lewis pairs chemistry offer important insights into their structural dynamics, while also pointing to new opportunities for photoactive materials with implications for fast responsive detectors.

Ultralong afterglow emissions due to room‐temperature phosphorescence (RTP) are of paramount importance in the advancement of smart sensors, bioimaging and light‐emitting devices. We herein present an efficient approach to achieve rarely accessible phosphorescence of heavy atom‐free organoboranes via photochemical switching of sterically tunable fluorescent Lewis pairs (LPs). LPs are widely applied in and well‐known for their outstanding performance in catalysis and supramolecular soft materials but have not thus far been exploited to develop photo‐responsive RTP materials. The intramolecular LPM1BNMnot only shows a dynamic response to thermal treatment due to reversible N→B coordination but crystals ofM1BNMalso undergo rapid photochromic switching. As a result, unusual emission switching from short‐lived fluorescence to long‐lived phosphorescence (rad‐M1BNM,τ_RTP=232 ms) is observed. The reported discoveries in the field of Lewis pairs chemistry offer important insights into their structural dynamics, while also pointing to new opportunities for photoactive materials with implications for fast responsive detectors.

We herein describe a new design principle to achieve B/N‐doped cyclophane where an electron‐donor block of three triarylamines (Ar₃N) and an acceptor block of three triarylboranes (Ar₃B) are spatially separated on opposite sides of the π‐extended ring system. DFT computations revealed the distinct electronic structure of theblock‐type macrocycleMC‐b‐B3N3with a greatly enhanced dipole moment and reduced HOMO–LUMO energy gap in comparison to its analogue with alternating B and N sites,MC‐alt‐B3N3. The unique arrangement of borane acceptor Ar₃B and amine donor Ar₃N components inMC‐b‐B3N3induces exceptionally strong intramolecular charge transfer in the excited state, which is reflected in a largely red‐shifted luminescence at 612 nm in solution. The respective linear open‐chain oligomerL‐b‐B3N3was also synthesized for comparison. Our new approach to donor–acceptor macrocycles offers important fundamental insights and opens up a new avenue to unique optoelectronic materials.

We herein describe a new design principle to achieve B/N‐doped cyclophane where an electron‐donor block of three triarylamines (Ar₃N) and an acceptor block of three triarylboranes (Ar₃B) are spatially separated on opposite sides of the π‐extended ring system. DFT computations revealed the distinct electronic structure of theblock‐type macrocycleMC‐b‐B3N3with a greatly enhanced dipole moment and reduced HOMO–LUMO energy gap in comparison to its analogue with alternating B and N sites,MC‐alt‐B3N3. The unique arrangement of borane acceptor Ar₃B and amine donor Ar₃N components inMC‐b‐B3N3induces exceptionally strong intramolecular charge transfer in the excited state, which is reflected in a largely red‐shifted luminescence at 612 nm in solution. The respective linear open‐chain oligomerL‐b‐B3N3was also synthesized for comparison. Our new approach to donor–acceptor macrocycles offers important fundamental insights and opens up a new avenue to unique optoelectronic materials.