ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Anion binding properties for pyrophosphate derived from a 2,6-diamidopyridinedipyrromethane macrocycle

Rui Yi, Xing-Li Liu, Zheng-He Tang, Chao Huang, Bi-Xue Zhu, and Chun Zhu

Key Laboratory of Macrocyclic and Supramolecular Chemistry of Guizhou Province, Guizhou University, Guiyang, People’s Republic of China

E-mail: bxzhu@gzu.edu.cn

Received: 15 November 2020  Accepted: 1 February 2021

Abstract:

A 2,6-diamidopyridinedipyrromethane macrocyclic receptor was prepared by a Schiff base condensation reaction. The structures of the free macrocycle and its complex with H₂P₂O₇²⁻ were analyzed by single crystal X-ray diffraction (SC-XRD). The stability constants for the binding of the receptor with tetrabutylammonium salts of HP₂O₇³⁻ were determined by isothermal titration calorimetry using acetonitrile solutions. According to the titration data, the receptor exhibited high affinity with HP₂O₇³⁻. The crystal structure analysis demonstrated that the neutral sandwich-type pyrophosphate complex was formed via the protonation of the macrocyclic receptor.

Keywords: Schiff base; Anion binding; Sandwich-type complex; Absorption spectrum; 1H NMR titration

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-021-01554-6

Chemical Papers 75 (8) 4405–4411 (2021)