Opportunities and Challenges in Applying Solid‐State NMR Spectroscopy in Organic Mechanochemistry

Advanced Materials, vol. 35, pp. e2304092

Abstract

In recent years it is shown that mechanochemical strategies can be beneficial in directed conversions of organic compounds. Finding new reactions proved difficult, and due to the lack of mechanistic understanding of mechanochemical reaction events, respective efforts have mostly remained empirical. Spectroscopic techniques are crucial in shedding light on these questions. In this overview, the opportunities and challenges of solid-state nuclear magnetic resonance (NMR) spectroscopy in the field of organic mechanochemistry are discussed. After a brief discussion of the basics of high-resolution solid-state NMR under magic-angle spinning (MAS) conditions, seven opportunities for solid-state NMR in the field of organic mechanochemistry are presented, ranging from ex situ approaches to structurally elucidated reaction products obtained by milling to the potential and limitations of in situ solid-state NMR approaches. Particular strengths of solid-state NMR, for instance in differentiating polymorphs, in NMR-crystallographic structure-determination protocols, or in detecting weak noncovalent interactions in molecular-recognition events employing proton-detected solid-state NMR experiments at fast MAS frequencies, are discussed.

Authors 4

1. Igor d’Anciães Almeida Silva

   Max Planck Institute for Chemical Energy Conversion

   Affiliation as printed

   Max Planck Institute for Chemical Energy Conversion Stiftstr. 34‐36 45470 Mülheim/Ruhr Germany

2. Ettore Bartalucci Aachen Institute of Technical and Macromolecular Chemistry

   Max Planck Institute for Chemical Energy Conversion · RWTH Aachen University

   Affiliation as printed

   Institute of Technical and Macromolecular Chemistry RWTH Aachen University Worringerweg 2 52074 Aachen Germany

   Max Planck Institute for Chemical Energy Conversion Stiftstr. 34‐36 45470 Mülheim/Ruhr Germany

   Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074 Aachen, Germany

3. Carsten Bolm corresponding Aachen Institute of Organic Chemistry

   RWTH Aachen University

   Affiliation as printed

   Institute of Organic Chemistry RWTH Aachen University Landoltweg 1 52074 Aachen Germany

   Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074 Aachen, Germany

4. Thomas Wiegand corresponding Aachen Institute of Technical and Macromolecular Chemistry

   Max Planck Institute for Chemical Energy Conversion · RWTH Aachen University

   Affiliation as printed

   Institute of Technical and Macromolecular Chemistry RWTH Aachen University Worringerweg 2 52074 Aachen Germany

   Max Planck Institute for Chemical Energy Conversion Stiftstr. 34‐36 45470 Mülheim/Ruhr Germany

   Institute of Technical and Macromolecular Chemistry, RWTH Aachen University, Worringerweg 2, 52074 Aachen, Germany