Type Of Aggregation And Emission Of Tetraphenylethlene Derivative

Among the aggregation luminesence materials,Tetraphenylethene(TPE)has been widely studied because of its various synthesis methods,strong modifiability and sensitive luminogenic response.Under some conditions,intermolecular interactions could result in aggregation or self-assembly that a common phenomenon in which molecules form definite structures,which is related to the spontaneous formation of nanostructures.Generally,the formation and growth of agglomerates are usually affected by intermolecular noncovalent interactions.TPEs are luminogenic molecules with aggregation-induced emission(AIE)nature,it's type of aggregation is very important.It is a great significance to study the type of aggregation of TPE for their AIE properties Due to the designability and adjustability of noncovalent interactions induce aggregation,it has attracted great attention in sensors,bioimaging,organic luminogenic materials and drug delivery.In this paper,we studied the type of aggregation and luminesence properties of TPE derivatives.In the first part,An alkoxyl linkage with four,five and six carbon length are employed to link the two neighboring ortho carbons of the two phenyl moieties at the same ethylene carbon of tetraphenylethylene framework TPEC4,TPEC5,TPEC6 were designed and optimized prepared.The compounds showed a unique red-blue-red shifted emission property in mixtures of H2O-DMSO with different water fractions Combing the Single crystal X-ray diffraction and powder X-ray diffraction analysis,we found that the blue shifted emission was attributed to the face-to-face stacking ordered arrangement of molecules in crystal state,which was driven by the C-H…?interaction together with hydrophobic.Generally,to TPEs,intermolecular C-H…?interactions were often found and considered as a way to control the rotation of the phenyl rings in crystal state,but as a driving force to aggregate were first proved.In the second part,a simple D-?-A structure TPE(TPEOMeCN)was designed and prepared.Two electron-rich methyloxyl phenyl groups and two electron acceptor cyanophenyl groups were composed of a network of alternative single and double bonds.In dilute solutions,the weak emissions of TPEOMeCN are dependent on the solvent polarity.In H2O-DMSO mixtures with high water fraction,the compound shows as a typical AIE lumingen.We found that the TICT and AIE emission could be in presence simultaneously H2O-DMSO mixtures(1:1,v/v).The comined emission of the TPEOMeCN could be readily tuned via changing the viscosities...