A Study On The Aromaticity Of [8]Circulune And Its Related Compounds

The concept of aromaticity is the most fundamental and widely studied subject in physical organic chemistry.Many experimental and theoretical probes have been developed to identify aromatic species,and to evaluate the degree of aromaticity.Because of the distinct properties of Circulenes,the aromaticity of[8]Circulenes aroused strong interest.The global aromaticity of pentalene and of its related compounds has been examined by the topological resonance energy(TRE)and magnetic resonance energy(MRE)methods.The local aromaticity was studied using bond resonance energy(BRE)and circuit resonance energy(CRE)methods.Moreover,the magnetic properties were studied employing the circuit current(CC)and ring current(RC)methods.The main points of this thesis are outlined as follows: In chapter 1 the origins and development of concepts related to aromaticity are presented.Several conventional indices of aromaticity,including geometric,energetic and magnetic indices were introduced and compared.Their strengths and weaknesses have been pointed out.Finally,the research significance of this paper is presented.we have described the history of synthesizing Circulenes and its related compounds.In chapter 2 the global aromaticity of Heteroannelated cyclooctatetraene derivatives is examined by means of the TRE and REPE methods.The local aromaticities are examined by the BRE and CRE methods.Our CC and RC results are then compared with the NICS results.In chapter 3 the global aromaticity of [8]circulune and Its Related Compounds is examined by means of the TRE,MRE and REPE methods.The local aromaticities are examined by the BRE and CRE methods.Their magnetic properties were analyzed using CC and RC methods.In chapter 4 the global aromaticity of tetraphenylene and Its Related Compounds is examined by means of the TRE,MRE and REPE methods.The local aromaticities are examined by the BRE and CRE methods.Their magnetic properties were analyzed using CC and RC methods.