Content may be subject to copyright.This is the peer reviewed version of the following article: [Frontispiece: Reactivity Studies on a Diazadiphosphapentale... ...This is the peer reviewed version of the following article: [Frontispiece: Reactivity Studies on a Diazadiphosphapentalene. Chemistry - A European Journal 22, 29 (2016)], which has been published in final form at https://doi.org/10.1002/chem.201682962. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions: https://authorservices.wiley.com/author-resources/Journal-Authors/licensing/self-archiving.html#3.