Primary amine recognition in water by a calix[6]aza-cryptand incorporated in dodecylphosphocholine micelles

Abstract

Water is a unique solvent and the design of selective artificial hosts that can efficiently work in an aqueous medium is a challenging task. It is known that the calix[6]tren zinc complex can recognize neutral guests in organic solvents. This complex was incorporated into dodecylphosphocholine micelles (DPC) and studied by NMR. The incorporated complex is able to extract selectively primary amines from the aqueous environment driven by an important hydrophobic effect which also affects the selectivity of the complex for these amines. This work shows how the incorporation of organo-soluble receptors in micelles can be an elegant and very efficient strategy to obtain water compatible nanosized supramolecular recognition devices which can be prepared via a straightforward self-assembly process.

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

“…In particular, among the best guests with divalent transition metal ions are primary amines. They are strongly bound to the funnel complex under various conditions, including organic solvents, water, and even micelles . With non-redox-active metal ions, methods of detections such as NMR, isothermal titration calorimetry, or fluorescence are classically used.…”

Submerging a Biomimetic Metallo‐Receptor in Water for Molecular Recognition: Micellar Incorporation or Water Solubilization? A Case Study

“…We recently described a very efficient means of incorporating a macrocyclic cationic metallo‐receptor into micelles . The receptor, a calix[6]arene‐based Zn II complex, was successfully incorporated into dodecylphosphocholine (DPC) micelles, and the incorporated complex was observed to be stable over a wide pH range.…”

“…We recently described av ery efficient means of incorporating am acrocyclic cationic metallo-receptor into micelles. [25] The receptor,acalix [6]arene-based Zn II complex, [30] was successfully incorporated into dodecylphosphocholine (DPC) micelles, and the incorporated complexw as observed to be stable over a wide pH range. We have now tested the same strategy with Rim 4 .D ue to its insolubility in water as an eutral compound, it was incorporated into the micelles at low pH, at which it is in protonated form.…”

“…However,n one of these funnel complexes are capableo fr ecognizing anions, even lipophilic ones. [25] Here, we report as tudy that compares two different strategies forw ater-solubilization of ar esorcinarene-based metalloreceptor ( Figure 1, right) for the recognition of small organic guestst hat are bound in their anionic form (Figure 1, right): direct solubilization of the ligand in water,w hich will then surround the metallo-receptor,o re ncapsulation into az witterion- Figure 1. Left:Awater-solublefunnel complex.…”

“…More recently, we have reported the successful incorporation of a calix[6]arene Zn II funnel complex into DPC micelles and have shown that the system retains its hosting properties towards amines at physiological pH. However, none of these funnel complexes are capable of recognizing anions, even lipophilic ones …”