The Synthesis Of 2-aminobenzoxazoles And BDOPV Conjugated Polymers

Oxidation coupling reaction because of its unique atom economy is widely used in organic synthesis and other fields. In the traditional work, the transition metal catalytic activation C-H to build all kinds of chemical bonds, such as C-C, C-N, C-O and C-S were developed. However the toxicity and expense of transition metals limit the practical applications. Thus, metal-free catalyzed oxidation coupling reaction has been the new hotspot in recent year. We have successfully developed the classic heterocyclic ionic liquid catalyst in the reaction of benzoxazoles and amine or amide. A series of 2-aminobenzoxazoles have been synthesized by our group and have broad application in the field of medicines and materials.With the rapid development of organic electronics in recent years, organic field effect transistor materials have been prospectively applied in all walks of life due to their tunable energy level, light weight and flexibility. However, the high mobility of organic material is infrequent. Therefore, exploring the high mobility of organic field effect transistor materials is a primary problem of chemists and materials scientists.The first chapter of this thesis includes three parts, The first part reviews the ionic liquids application of constructing chemical bonds such as C-C, C-N, C-O and C-S. the synthetic methods of 2-aminobenzoxazoles which had been reported were summarized in the second part. The last past mainly introduces the structure and principle of organic field effect transistor and the research development of Indigo compounds in organic field effect transistor.In the second chapter of this thesis, we presented an efficient, green and mild method for the synthesis of 2-aminobenzoxazoles, using IL 1-butylpyridinium iodide as the catalyst and TBHP being the oxidant. Compared with previous synthesis method, this work proceeded smoothly for 3.5 h at room temperature and gave the desirable 2-aminobenzoxazole derivatives with good to excellent yields(82%- 97%). The catalyst 1-butylpyridinium iodide can be easily recycled and reused with similar efficacies for at least four cycles.In the third chapter of this thesis, a transition metal-free method for the direct amination of benzoxazoles using formamides as nitrogen sources is reported, which was catalyzed by an inexpensive and environmentally friendly IL 1-butylpyridinium iodide and gave the 2-aminobenzoxazole derivatives with moderate to good yields.In the last chapter of this thesis, two types of donor-acceptor conjugated polymers(ClBDOPV, N-BDOPV) have been synthesized for usage in organic field-effect transistors. In addition, the photophysical and electrochemical, thermodynamic properties of polymers have been discussed.