How do fluoride ions bind to tetrathiacalix[2]arene[2]triazines?. Issue 22 (28th May 2020)

• Record Type: Journal Article
• Authors: Pisagatti, Ilenia; Manganaro, Nadia; Mirabella, Chiara F.M.; Pappalardo, Andrea; Trusso Sfrazzetto, Giuseppe; Nastasi, Francesco; Notti, Anna; Parisi, Melchiorre F.; Gattuso, Giuseppe
• Is Part Of: Tetrahedron letters. Volume 61:Issue 22(2020)
• Publication Date: 2020-05-28
• Subjects: Metacyclophanes -- Calix[2]arene[2]triazine -- Thiacalixarenes -- Anion binding -- σ-Complex; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tetlet.2020.151911
• Languages: English
• ISSNs: 0040-4039

Abstract

Graphical abstract: Highlights: Two novel tetrathiacalix[2]arene[2]triazines have been synthesized. They recognize selectively fluoride over other halide ions. Fluoride ions form a Meisenhaimer-type σ-complex with the two macrocycles. Abstract: Two novel tetrathiacalix[2]arene[2]triazines 1a, b have been synthesized and investigated as halide ionophores. UV–vis titrations showed that these macrocycles have a high affinity for fluoride over other halide ions; 1 H NMR spectroscopy revealed that only upon fluoride (and not chloride or bromide) ion addition does the spectrum undergo a dramatic loss of symmetry. Finally, a comprehensive DFT (B3LYP/6–311 + G(d, p)) investigation suggested that fluoride ions likely form σ-complexes upon binding to 1a and 1b .