Host-Guest Chemistry: Oxoanion Recognition Based on Combined Charge-Assisted C−H or Halogen-Bonding Interactions and AnionAnion Interactions Mediated by Hydrogen Bonds

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• 作者：Lidia Gonzá ; lez ; Dr. Fabiola Zapata ; Dr. Antonio Caballero ; Prof. Pedro Molina ; Prof. Carmen Ram&#237 ; rez de Arellano ; Prof. Ibon Alkorta and Prof. José ; Elguero
• 刊名：Chemistry - A European Journal
• 出版年：2016
• 出版时间：May 23, 2016
• 年：2016
• 卷：22
• 期：22
• 页码：7533-7544
• 全文大小：4794K
• ISSN：1521-3765

文摘

Several bis-triazolium-based receptors have been synthesized and their anion-recognition capabilities have been studied. The central chiral 1,1′-bi-2-naphthol (BINOL) core features either two aryl or ferrocenyl end-capped side arms with central halogen- or hydrogen-bonding triazolium receptors. NMR spectroscopic data indicate the simultaneous occurrence of several charge-assisted aliphatic and heteroaromatic C−H noncovalent interactions and combinations of C−H hydrogen and halogen bonding. The receptors are able to selectively interact with HP₂O₇³⁻, H₂PO₄⁻, and SO₄²⁻ anions, and the value of the association constant follows the sequence: HP₂O₇³⁻>SO₄²⁻>H₂PO₄⁻. The ferrocenyl end-capped 7²⁺⋅2 BF₄⁻ receptor allows recognition and differentiation of H₂PO₄⁻ and HP₂O₇³⁻ anions by using different channels: H₂PO₄⁻ is selectively detected through absorption and emission methods and HP₂O₇³⁻ by using electrochemical techniques. Significant structural results are the observation of an anion⋅⋅⋅anion interaction in the solid state (2:2 complex, 6²⁺⋅[H₂P₂O₇]²⁻), and a short C−I⋅⋅⋅O contact is observed in the structure of the complex [8²⁺][SO₄]_0.5[BF₄].