Towards the Stable Binding of Mercury: Synthesis and Functionalization of Dibenzyldiazabicyclononane Scaffolds

Abstract

A universally applicable synthesis route for the preparation of functionalized diazabicyclononane compounds was elaborated starting from a readily available 1,5‐diphenyl‐3,7‐diazabicyclo[3.3.1] nonan‐9‐ol by alkylation of both secondary amines with modified benzyl residues containing a bromo, trimethylstannyl, trimethylsilyl, and pinacolboranyl residue. High yields (65‐88%) were achieved, supporting the intended purpose of these compounds: efficient mercuration reactions to stably bind Hg2+. Finally, the C‐9 position of two functionalized diazabicyclononanes was further modified by introducing an azide functionality. This enables the conjugation to biomolecules of interest via click chemistry combined with a tracking by the introduced mercury isotopes.