Synthesis of Dansyl-Substituted Cryptands Containing Triaza cycloalkane Moieties and their Evaluation as Fluorescent Chemosensors

A method for the synthesis of a new family of cryptands containing 1,4,7-triazacyclononane and 1,5,9-triazacyclododecane moieties and dansyl fluorophore groups has been elaborated starting from free triazacycloalkanes and employing Pd(0)-catalyzed amination at the macrocyclization step. The dependence of the products yields on the nature of reagents has been established. The majority of synthesized macrobicycles have been evaluated as possible chemosensors for detecting metal cations. Compound comprising 1,4,7-triazacyclononane and dioxadiamine linker proved to be a prospective colorimetric sensor for Cu(II) by changing its absorption spectrum in the presence of this cation, while other cryptands demonstrated full quenching of fluorescence in the presence of Cu(II) and Al(III) what makes them promising fluorescent molecular probes for these metals.