Synthesis, Structure, and Properties of Corona[6]arenes and Their Assembly with Anions in the Crystalline State

• Published in: Journal of organic chemistry 2018-02, Vol.83 (3), p.1502-1509
• Main Authors: Zhao, Meng-Yao, Wang, De-Xian, Wang, Mei-Xiang
• Format: Article
• Language: English
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/acs.joc.7b03136

The synthesis, conformational structure, electronic property, and anion complexation of novel coronarenes were systematically studied. A number of corona[4]­arene[2]­tetrazines that contain different combinations of nitrogen atoms with O, S, SO2, and CH2 as bridging units were synthesized conveniently by means of a fragment coupling strategy based on efficient nucleophilic aromatic substitution reaction of easily available aromatic dinucleophiles and 3,6-dichlorotetrazine. The resulting macrocycles adopt crownlike conformational structures with the nitrogen bridge(s) forming conjugation with carbonyl and the other heteroatom linkages with tetrazine. CV and DPV measurements showed that the tetrazine-bearing coronarenes were electron deficient with reduction potentials ranging from −896 to −960 mV. Owing mainly to noncovalent anion−π attractive interactions, N2,O4-corona­[4]­arene­[2]­tetrazine formed complexes with anions of varied geometries and shapes yielding diverse assembled structures in the solid state.