Pyrazaboles and pyrazolylboranes

The synthesis, reactivity, and properties of pyrazaboles and pyrazolylboranes have been reviewed with special attention to the NMR properties and X-ray structures. 104 X-ray structures are presented and 150 references are cited, which is a significant expansion of previous reviews. It appears that several items are incomplete and others deserve further development indicating than the field of pyrazaboles and of pyrazolylboranes needs new research contributions in particular in the field of coordination chem-istry, a field that is clearly underdeveloped.(c) 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).