Analyte

Physics

Isomerization

Pathology

Physical chemistry

Catalysis

Organic chemistry

Nucleophile

Chemistry

Alternative medicine

Combinatorial chemistry

Reactivity (psychology)

Aldehyde

Alkyl

Aryl

Molecular switch

Molecule

Quantum mechanics

Catalytic cycle

Medicine

Photochemistry

Fluorescence

Journal of the American Chemical Society

Upon light-induced isomerization, diarylethenes (DAEs) equipped with reactive aldehyde moieties rearrange selectively in the presence of amines, accompanied by decoloration. In a comprehensive study, the probe structure was optimized with regard to its inherent reactivity in the nucleophile-triggered rearrangement reaction. Detailed structure–reactivity relationships could be derived, in particular with regard to the type of integrated (het)aryl moieties as well as the location of the formyl residue, and the probes' intrinsic reactivity with primary and secondary amines was optimized. Utilizing an ancillary base, the initially formed rearrangement product can engage in a subsequent catalytic cycle, leading to an amplified decoloration process. This additional catalytic pathway allows us to enhance the sensitivity of our method and successfully discriminate between amines and thiols. Moreover, probes that exhibit strong analyte-induced fluorescence modulation have been designed to further decrease the detection limit by using a more sensitive read-out. The optimized DAE probes are promising molecular components for future programmable sensing materials and devices.

Sensitive Assays by Nucleophile-Induced Rearrangement of Photoactivated Diarylethenes