<p>Reactive carbonyl compounds are common pollutants and endogenous metabolites that are often toxic at high concentrations. Removal/detoxification of carbonyl compounds requires selective small molecule scavengers; however, few molecules suitable for this task have been fully characterised. Here, we report NMR-based kinetic and selectivity studies on representative 1-amino-but-3-enes, which are reported to be selective formaldehyde scavengers. Our experiments reveal that 1-amino-but-3-enes containing phenyl groups at position 1 react with formaldehyde via a 2-aza-Cope rearrangement. However, they also react with other carbonyl compounds, including the biologically relevant 1,2-dicarbonyl compound glyoxylic acid. The most efficient and promiscuous scavenging compound promoted the growth of <i>Escherichia coli</i> cells, while studies on cell lysate revealed potential for aldehyde sequestration. Overall, our analyses suggest that 1-amino-but-3-enes can be used to scavenge a variety of toxic carbonyl compounds and may be used in imaging and quantification studies, as well as for biomedical applications.</p><p></p>