Tripodal tris(diamide) receptor having H-bond donors and acceptors on trindane platform for H2PO4− recognition
- 4 Downloads
A new C3v-symmetric tris(diamide) receptor 2 possessing both H-bond donor and acceptor sites was synthesized and characterized by various spectral data. The anion recognition ability of receptor 2 was investigated by 1H NMR in DMSO-d6. Among the tested anions (F−, Cl−, Br−, I−, NO3−, HSO4− and H2PO4−), the receptor 2 shows high selectivity towards H2PO4− anion. The amide-NH protons peaks of receptor 2 at δ 10.42 and δ 8.23 ppm were broadened and shifted to downfield region in the presence of H2PO4−. The appended arms with tris(diamide) H-bond donors and pyridine H-bond acceptors of receptor 2 provide a preorganized cavity to encapsulate the H2PO4− through multiple hydrogen bonds. The 1H NMR titration measures the binding constant (Ka) of 293 M−1 for the host–guest complex formed between receptor 2 and H2PO4−. Further, the possible 3D structure of receptor 2 and its complex with H2PO4− anion was proposed through density functional theory method.
KeywordsTrindane Tripodal anion receptor Tris(diamide) H2PO4− 1H NMR DFT
This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (Grant No. NRF-2017R1D1A1B03032108).
- 8.Reinoso-García, M.M., Dijkman, A., Verboom, W., Reinhoudt, D.N., Malinowska, E., Wojciechowska, D., Pietrzak, M., Selucky, P.: Metal complexation by tripodal N-acyl (thio) urea and picolin (thio) amide compounds: synthesis/extraction and potentiometric studies. Eur. J. Org. Chem. 2005, 2131–2138 (2005)CrossRefGoogle Scholar
- 16.Choi, H.-J., Song, J., An, C.Y., Nguyen, Q.-T., Kim, H.-S.: Diastereofacial-selective synthesis of the trindane-based molecular scaffold cis, cis, cis-2,5,8-tribenzyltrindane-2,5,8-tricarboxylate and an arylamine analogue for the construction of C3v-symmetric architectures. Synthesis 2007, 3290–3294 (2007)CrossRefGoogle Scholar