Unleashing the Potential of 17 O NMR Spectroscopy Using Mechanochemistry.

17 O NMR spectroscopy has been the subject of vivid interest in recent years, because there is increasing evidence that it can provide unique insight into the structure and reactivity of many molecules and materials. However, due to the very poor natural abundance of oxygen-17, 17 O labeling is generally a prerequisite. This is a real obstacle for most research groups, because of the high costs and/or strong experimental constraints of the most frequently used 17 O-labeling schemes. Here, we show for the first time that mechanosynthesis offers unique opportunities for enriching in 17 O a variety of organic and inorganic precursors of synthetic interest. The protocols are fast, user-friendly, and low-cost, which makes them highly attractive for a broad research community, and their suitability for 17 O solid-state NMR applications is demonstrated.