Engineering 1,3-Alternate Calixcarbazole for Recognition and Sensing of Bisphenol F in Water

Herein, we report a carbazolyl tubular macrocycle (3), which possesses a "π-tube" capable of encapsulating and sensing bisphenol F (BPF), which is a toxic industrial material. In this work, the synthesis of 3, its conformation in solution as well as its binding property to BPF have been investigated. Nuclear magnetic resonance (NMR), ultraviolet-visible light (UV-vis), fluorescence spectra, and molecular modeling studies reveal that the "π-tube" of 3 in 1,3-alternate conformation could encapsulate BPF with 1:1 binding stoichiometry in water, with its orthogonal tweezers sandwiching the two phenol units of BPF. Moreover, 3 could serve as a sensitive fluorescent probe for BPF (limitation of detection = 157 nM).