Second Generation Calix[6]trenamides – Highly Selective Graftable Receptors for Neutral Guests and Contact Ion Pairs

Abstract

With the aim of designing graftable calix[6]tren‐based receptors, calix[6]trenamides decorated with an appended functional arm were synthesized through [1+1] macrocyclization reactions between calix[6]trisamines and NTA‐lysine derivatives. NMR spectroscopy and ESI‐MS studies showed that one of these calix[6]trenamides, 5, behaves as a unique heteroditopic receptor towards charged or neutral species. Notably, it can selectively bind contact ammonium fluoride salts through a highly cooperative process. In addition, acid–base control of its binding properties was clearly evidenced. This second generation of graftable receptors opens new perspectives in the design of sensors for charged or neutral species.

Immobilization of Monolayers Incorporating Cu Funnel Complexes onto Gold Electrodes. Application to the Selective Electrochemical Recognition of Primary Alkylamines in Water

“…To this aim, we used a monofunctionalized calix[6]­tren amide precursor ( 1 ) that was recently reported by some of us (Scheme ). Reduction of the amido and carbamate groups of 1 with BH 3 ·THF led to the corresponding monofunctionalized calix[6]­tren ( 2 ) in 79% yield. To obtain a derivative that could be grafted through a CuAAC “click” reaction, an azide function was then introduced at the level of the appending arm.…”

“…Compound 1 and N -dansyl-1,6-hexanediamine were prepared according to procedures previously described in the literature. , All reactions were conducted under an inert atmosphere.…”

Efficient hydrogen bonding recognition in water using aryl-extended calix[4]pyrrole receptors

“…Aiming at mimicking the binding behavior of enzymes, several aqueous and water soluble synthetic receptors possessing more or less open aromatic cavities with converging polar groups have been reported by the groups of Davis,6–8 Jiang,9–11 and Jabin,12,13 among others. The obtained binding results demonstrated that the combination of a functionalized aromatic cavity (binding site with a low dielectric constant) displaying multiple open portals (cages or tubes) with converging polar groups is a successful strategy for achieving effective binding of neutral polar molecules in aqueous media and water with synthetic receptors (Fig.…”

“…The incorporation of p -methyl substituents in the meso -phenyl groups of the receptors aimed at increasing the depth of their aromatic cavities. We employed pyridinium groups as water-solubilizing units, based on their performance for solubilizing related resorcinarene derived cavitands in water 11,13,22. We located the water solubilizing groups at the lower rim of the receptors, distal from the polar aromatic binding site.…”

Switchable Wettability Sensor for Ion Pairs Based on Calix[4]azacrown Clicking

“…The design and application of ion-pair receptors, capable of the simultaneous coordination of both anionic and cationic guest species, has attracted significant interest because of their potential application as novel extraction reagents for the purification of pernicious substances in the environment. − Recently, this exciting area of ion-pair recognition has been concerned with the syntheses of host molecules that comprise binding sites for both anionic and cationic guests . Calixcrowns make up a family of calixarenes that exhibit a superior recognition of ion pairs via the cooperation of both the calixarene and crown moieties. , Beer and co-workers synthesized calixcrowns with binding sites for both anionic and cationic guest species as ion-pair receptors. ,, …”