Lactam-fused tropolones: a new tunable, environmentally sensitive fluorophore class

Fluorescent small-molecules capable of altering their profiles in response to environmental changes are exceptionally valuable tool compounds throughout the scientific community. The following manuscriipt describes a new class of fluorescent small molecules based on lactam-fused tropolones that are responsive to a dynamic range of environmental changes. These molecules can be easily obtained through a rapid annulation procedure between appropriately functionalized tropolones and primary amines, which is often complete within minutes at room temperature. Molecules generated through this approach have been identified with fluoresence emission across the visible light spectra, and can be tuned based on either the tropolone or amine component. They are also highly responsive to changes in solvent, pH, and certain divalent metal ions. Tropolone-fused lactams thus represent a new class of tunable fluorescent small molecules that could find value throughout the scientific community. Lactam-fused tropolones are easily accessible, environmentally-responsive fluorophores with broad emissions profiles.