Electrochemical labelling of hydroxyindoles with chemoselectivity for site-specific protein bioconjugation.

Electrochemistry has recently emerged as a powerful approach in small-molecule synthesis owing to its numerous attractive features, including precise control over the fundamental reaction parameters, mild reaction conditions and innate scalability. Even though these advantages also make it an attractive strategy for chemoselective modification of complex biomolecules such as proteins, such applications remain poorly developed. Here we report an electrochemically promoted coupling reaction between 5-hydroxytryptophan (5HTP) and simple aromatic amines-electrochemical labelling of hydroxyindoles with chemoselectivity (eCLIC)-that enables site-specific labelling of full-length proteins under mild conditions.

Probing promoting effects of alkali cations on the reduction of CO at the aqueous electrolyte/copper interface.

The catalytic selectivity and reactivity of an electrocatalytic interface can profoundly depend on the identity of the supporting electrolyte's cation. In the case of CO reduction on copper electrodes, these cation effects have been utilized to suppress undesired hydrogen evolution and to promote the formation of C reduction products. However, to more effectively steer the catalytic selectivity of the electrolyte/copper interface by cations, it is crucial to reveal the various physical mechanisms by which cations impact the catalytic properties of this prototypical interface for CO reduction.