Molecular Engineering On Spirobifluorene-based Tic-tac-toe Nanogridarenes

Exploring nanoscale organic conjugated molecules with clear shapes has important scientific significance in the field of organic aromatics chemistry.Due to novel structures,excellent properties and functions,they can be well applied in the field of organic semiconductor materials.The emerging Nanogridarenes are one of the them,the existing types of nanogridarenes include ladder-type,windmill-type and diamond-type at present.Unlike traditional macrocycles,they have significantly regular and interconnected characteristics structure,which with a clear side length and vertex.And they also have good thermal stability,electrochemical stability and spectral stability that can be applied to organic electronic devices.However,the extendible vertices and extendible dimensions of nanogridarenes above are still limited,and the conformations of nanogridarenes that based on diaryl fluorine are so much.Therefore,this paper innovates a new eight-arm extendible gridarene to enrich the geometric types of nanogridarenes,we stabilize the configuration by introducing spirofluorene and carries out a series of research work focusing on the construction of spirobifluorene-based Tic-tac-toe nanogridarene.Starting from organic semiconductor materials,we introduced the classification of organic conjugated macrocycles and nanogridarenes in detail,and compared the differences between gridding and cyclization.Last we briefly described the research and development of spirobifluorene.The major research contents and results include the following:First,we described the ideal molecular structure of spirobifluorene-based Tic-tac-toe nanogridarene with eight-arm extensibility and studied their theoretical properties.The innovation lies in introducing cruciform and crossed spirobifluorene as the only building block.Then,we designed and analyzed the inverse synthesis paths.After experimental exploration,the Suzuki coupling is abandoned and the tic-tac-toe nanogrids were successfully synthesized by the Yamamoto coupling reaction.Second,the study found that in the reaction system products have nanogrids and chain polymers at the same time.We purified [n] GSBF(n=3,4,5)and identified structure by mass spectrometry and nuclear magnetic characterization analysis.And we obtained [3] GSBF at a high yield which only a separable isomer,in fact the tic-tac-toe nanogrids [4]GSBFs are by-products,which are only two separable isomer.Third,a series of characterization methods were used to prove the electrochemical stability,thermal stability and other excellent properties of spirobifluorene-based nanogrids.It was observed that both two isomers of [4]GSBF have green band in their emission spectra,and two possible reasons for this phenomenon were analyzed.Device experiments showed [3]GSBF has the potential to be applied to organic electronic devices.In this paper,spirobifluorene-based Tic-tac-toe nanogridarene with the characteristics of eight-arm extensibility and multi-dimensional extensibility enrich the geometric types of organic nanogridarenes This work will provide a new idea for the design of one-dimensional,two-dimensional and three-dimensional nanopolymers materials in the future.