Merging tetraphenylethylene(TPE)into cyclic skeletons endows fluorescent sensing capabilities for pillar[6]arenes aggregates,but results in losing their host-vip recognition function in dilute solutions.Inspired by ...Merging tetraphenylethylene(TPE)into cyclic skeletons endows fluorescent sensing capabilities for pillar[6]arenes aggregates,but results in losing their host-vip recognition function in dilute solutions.Inspired by natural enzymes,here we describe a series of TPE-based cyclo[6]arenes(termed TPz,TDz,and TTz)with endo-functionalized cavities containing inward-directed diazine motifs(pyrazine,pyridazine,and phthalazine)that act as hydrogen-bond acceptor sites.Combining electrostatic potential analysis and host-vip binding studies reveals that subtle variations in these diazine motifs substantially affect charge distribution and hydrogen-bond interactions within the internal microenvironment.These differences translate into disparate host-vip affinities,with TTz exhibiting the optimal performance.Unlike TPz,which recognizes vips only in aggregate states,1,2-diazine-modified TDz and TTz possess dual-state recognition functionality.They enable size-selective binding for cationic vips in dilute solutions and sensitive fluorescence detection of nitrophenol pollutants in aggregate states through a photoinduced electron transfer-driven static quenching mechanism.This study underscores the potential of 1,2-diazine motifs as transformative hydrogen-bond acceptors for biomimetic host models with emergent properties.展开更多
基金support was provided by the National Natural Science Foundation of China(22401064 and 22161017)the Innovational Fund for Scientific and Technological Personnel of Hainan Province(KJRC2023D34)+1 种基金the Hainan Provincial Natural Science Foundation of China(224QN184)the Research Start-up Fund of Hainan University(KYQD(ZR)23037).
文摘Merging tetraphenylethylene(TPE)into cyclic skeletons endows fluorescent sensing capabilities for pillar[6]arenes aggregates,but results in losing their host-vip recognition function in dilute solutions.Inspired by natural enzymes,here we describe a series of TPE-based cyclo[6]arenes(termed TPz,TDz,and TTz)with endo-functionalized cavities containing inward-directed diazine motifs(pyrazine,pyridazine,and phthalazine)that act as hydrogen-bond acceptor sites.Combining electrostatic potential analysis and host-vip binding studies reveals that subtle variations in these diazine motifs substantially affect charge distribution and hydrogen-bond interactions within the internal microenvironment.These differences translate into disparate host-vip affinities,with TTz exhibiting the optimal performance.Unlike TPz,which recognizes vips only in aggregate states,1,2-diazine-modified TDz and TTz possess dual-state recognition functionality.They enable size-selective binding for cationic vips in dilute solutions and sensitive fluorescence detection of nitrophenol pollutants in aggregate states through a photoinduced electron transfer-driven static quenching mechanism.This study underscores the potential of 1,2-diazine motifs as transformative hydrogen-bond acceptors for biomimetic host models with emergent properties.
