“…Given the numerous MS-based studies on organometallic ion chemistry related to catalysis, the scope of this review is limited to metal-catalyzed transformations of carboxylic acids and their derivatives of relevance to organic synthesis. Fragmentation reactions of coordinated carboxylates that involve redox chemistry and give rise to metal anions (Curtis et al, 2010(Curtis et al, , 2011Attygalle, Axe, & Weisbecker, 2011;Butson, Curtis, & Mayer, 2016) or metal-CO 2 complexes (Dossmann et al, 2012;Rodriguez-Blanco et al, 2013;Miller et al, 2014;Blaziak et al, 2018;Jestila & Uggerud, 2018;Miller & Uggerud, 2018;Jestila et al, 2020), although fascinating in their own right, are not reviewed. Carboxylic acids and their derivatives that contain multiple functional groups (e.g., peptides and proteins) are not considered.…”