Isotope Labeling Reveals Fast Atomic and Molecular Exchange in Mechanochemical Milling Reactions

Abstract

Using tandem in situ monitoring and isotope-labeled solids, we reveal that mechanochemical ball-milling overcomes inherently slow solid-state diffusion through continuous comminution and growth of milled particles. This process occurs with or without a net chemical reaction and also occurs between solids and liquid additives which can be practically used for highly efficient deuterium labeling of solids. The presented findings reveal a fundamental aspect of milling reactions and also delineate a methodology that should be considered in the study of mechanochemical reaction mechanisms.

Mechanochemistry for Synthesis

“…[89] Angewandte Chemie carboxylic and boronic acids using H 2 17 O, [94] while Lukin et al demonstrated rapid deuteration with D 2 O. [95]…”

Direct Mechanocatalysis: Using Milling Balls as Catalysts

“…With aw ise choice of laser parameters and reactants, however, it is possible to follow directm echanocatalysis reaction with both in situ techniques. [33] Both of these methods, however,c an only give indications towards the mechanismso fd irect mechanocatalytic reactions. To fully elucidate the mechanisms, one needs to closer investigate the milling balls urface in the moment of impact.T his on the other hand seems hardly feasible and thus ap roper investigation needs to heavily rely on ex-situd ata.…”

Mechanochemistry for Synthesis

“…for efficient 17 O‐labeling of hydroxides, oxides, carboxylic and boronic acids using H 2 17 O, while Lukin et al. demonstrated rapid deuteration with D 2 O …”