Synthesis of i‐Corona[6]arenes for Selective Anion Binding: Interdependent and Synergistic Anion–π and Hydrogen‐Bond Interactions

• Published in: Angewandte Chemie Vol. 132; no. 52; pp. 23924 - 23931
• Main Authors: Zhuang, Sheng‐Yi, Cheng, Ying, Zhang, Qian, Tong, Shuo, Wang, Mei‐Xiang
• Format: Journal Article
• Language: English
• Published: 21.12.2020
• Subjects: anion recognition; anion–π interactions; coronaarene; hydrogen bonding; macrocycles
• ISSN: 0044-8249; 1521-3757
• DOI: 10.1002/ange.202008997

i‐Corona[3]arene[3]tetrazines were synthesized from the nucleophilic aromatic substitution reaction of resorcinol and its derivatives with 3,6‐dichlorotetrazine in a one‐pot fashion under mild conditions. All of the resulting macrocycles adopted 1,3,5‐alternate conformation irrespective of the nature of the substituents on both upper‐ and lower‐rims. i‐Corona[3]arene[3]tetrazine was found to self‐regulate its macrocyclic conformation and cavity to recognize anions with binding constants spanning from 26 M−1 to 2.2×103 M−1 depending on the structure of the anions. The selective binding resulted from a significant interdependent and synergistic effect between multiple tetrazine π/anion and Caryl–H/anion hydrogen bond interactions. Taking advantage of synergistic effect revealed, a cyanobenzene‐embedded i‐corona[3]arene[3]tetrazine was designedly synthesized and highly selective and very strong affinity toward nitrate with a binding constant of 2.2×105 M−1 was achieved. i‐Corona[3]arene[3]tetrazines were synthesized straightforwardly from the nucleophilic aromatic substitution reaction of resorcinol and its derivatives with 3,6‐dichlorotetrazine in a one‐pot fashion under mild conditions. They can regulate their macrocyclic conformation and cavity structures to recognize anions by forming interdependent and synergistic anion–π/and hydrogen bond interactions.