Synthesis, Structure And Property Of Homo Coronarenes

Anion-?interactions are now recognized as general and useful non-covalent attraction force between anions and electron-deficient?systems.Exploration of the nature and application of anion-?in the molecular recognition remains a challenging issue.Tailor-made macrocycles,which play a pivotal role in supramolecular chemistry,are excellent models to study the non-covalent interactions between hosts and guests.This thesis mainly focuses on the development of novel homo coronarenes and the selective recognition between homo coronarenes and anions.Exploiting the phenylenedimethanol and 3,6-dichlorotetrazine,,we have developed[3+1]fragment coupling approach on the basis of nucleophilic aromatic substitution reaction,which allows us to achieve a series of?CH₂O?₄-homocorona[2]arene[2]tetrazines.The homo coronarene derived from phenylenedimethanol and 3,6-dichlorotetrazine contains electron-deficient rectangular box-like cavites and the tetrazine moieties are face-to-face paralleled.?CH₂O?₄-homocorona[2]arene[2]tetrazines showed excellent selectivity in anion recognition owing to the shape complementarity between host and guest while forming anion-?interactions.We achieved?CH₂S?₄-homocorona[2]arene[2]tetrazines in both the one-pot fashion and[3+1]fragment coupling.By changing the bridge atom from oxygen to sulfur,the conformations of the homocoronarenes become more flexible conformation.The cavities of the?CH₂S?₄-homocorona[2]arene[2]tetrazines are larger and more election-defficient.We synthesized?CH₂S?₄-homocorona[2]arene[2]pyridazines by the inverse electron demanding Diels-Alder reaction of?CH₂S?₄-homocorona[2]arene[2]tetrazines.?CH₂S?₄-homocorona[2]arene[2]pyridazines could form 1:1 complex with Hg²⁺in acetonitrile,and the stability constant is?2.54±0.12?×10⁴M^-1.Starting from the phenylenedithiol and the trimer formed by phenylenedimethol and3,6-dichlorotetrazine,we constructed a series of homo coronarenes containing mixed bridging atoms.By the selective oxidation of the thioether moieties,we achieved the sulfoxide/sulfone bridged homo coronarenes.?CH ₂O?₂,?CH₂S?₂-homocorona[2]arene[2]tetrazines have the ability to recognize azide selectively while the mono-sulfoxide bridged homocorona[2]arene[2]tetrazine could recognize thiocyanate selectively.In summary,we have established and developed one-pot and[3+1]fragment coupling reaction strategy to the synthesis of the homo coronarenes.We have demonstrated the selective oxidation of the thioether moiety of homo coronarenes as well.The cavity size,the electronic feature and even the propert y in molecular recognition of the homo coronarenes could be tuned by the substitution pattern of phenylene subunits and the bridging atoms.The synthesis and modification of homo coronarens are simple and efficient.The conformation and cavity size could be tuned conveniently.With the study proceeding,it is believed that the application of homo coronarenes in supramolecular chemistry will become more abundant.