⁹⁹TcO₄⁻: Selective Recognition and Trapping in Aqueous Solution

Abstract

Too hot to handle: Unprecedented affinity and specificity for (99)TcO(4)(-) in aqueous solution was shown with the p-xylyl azacryptand in the hexaprotonated form. A crystal structure of the complex reveals how the anion fits within the cavity of the cage, and the formation of multiple H-bond interactions with protonated amino groups stabilize the adduct.

Molecular recognition and activation by polyaza macrocyclic compounds based on host–guest interactions

“…12a) (Fig. 37 Then they have improved the molecular system by introducing a fluorescent signaling unit in the receptor's skeleton, that is, using L 15 to encapsulate TcO 4 - (Fig. (Fig.…”

Highly Selective Colorimetric and Luminescence Response of a Square-Planar Platinum(II) Terpyridyl Complex to Aqueous TcO4–

“…However, the sensitivity of the cryptand to ClO 4 − and other tetrahedral, singly charged oxoanions other than the structural surrogate ReO 4 − was not reported. 24 One practical drawback of these molecular recognition receptors is related to their typically elaborate synthesis and purification.…”

An Ultrafast Molecular‐Rotor‐Based Fluorescent Turn‐On Sensor for the Perrhenate Anion in Aqueous Solution

“…Of these, some supramolecular hosts have been designed to bind perrhenate in a very selective manner, however, their operations are limited to organic media or organic/aqueous mixtures . To overcome this limitation, recently, some supramolecular receptors have been synthesized that utilize a combination of electrostatic interactions and multiple hydrogen‐bonding interactions and, more recently, halogen bonding to achieve the selective binding of the perrhenate anion in aqueous media . To exploit the selective binding of the designed supramolecular host with the perrhenate/pertechnetate anion for its analytical detection, one such receptor molecule was functionalized with a fluorophore, anthracene, which signaled the binding of the perrhenate/pertechnetate to the receptor molecule through a decrease in its fluorescence intensity .…”