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Updated: Mar 20, 2026

Synthesis of 1,2-Azaborines and the Preparation of Their Protein Complexes with T4 Lysozyme Mutants
Published on: March 25, 2017
Straightforward and Controlled Shape Access to Efficient Macrocyclic Imidazolylboronium Anion Receptors
Momar Toure1, Laurence Charles2, Christophe Chendo2
1Aix Marseille Université, Centrale Marseille, CNRS, iSm2 UMR 7313, 13397, Marseille, France.
Abstract:
A straightforward synthesis of air- and water-stable bis-cationic macrocyclic imidazolylboronium anion receptors is described herein. By taking advantage of the bulky and rigid 9-borabicyclo[3.3.1]-nonane (9-BBN) attaching point and a well-designed bis-imidazolylaryl, highly stable dimeric imidazolylboronium macrocycles were synthesized. Additionally, NMR spectroscopy ((1) H, DOSY, and HOESY), mass spectrometry (MS), and X-ray diffraction studies revealed that these macrocyclic scaffolds can bind several monoanions with high association constants in DMSO, and are particularly sensitive for the MS detection of anions (with concentrations in the nm range). This anion/receptor interaction involves eight C-H binding sites, which include Csp2 -H and unusual Csp3 -H hydrogen-bonding donors.
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