Persistence of a Ru3(μ‐CO)3(CO)5 Cluster Bound to a PNNP “Expanded Pincer” Ligand in Different Protonation States

• Published in: European journal of inorganic chemistry Vol. 2022; no. 22
• Main Authors: Beek, Cody B., Killian, Lars, Lutz, Martin, Broere, Daniël L. J.
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 08-08-2022
• Subjects: Carbon monoxide; Cluster compounds; Clusters; Cooperative effects; Expanded pincer ligands; H2 activation; Inorganic chemistry; Ligands; Multimetallic chemistry; Protonation; Ruthenium
• ISSN: 1434-1948; 1099-0682
• DOI: 10.1002/ejic.202200191

We report the synthesis and characterization of Ru3(μ‐CO)3(CO)5‐type cluster complexes bound to a dinucleating PNNP ‘expanded pincer’ ligand. Each bidentate PN pocket of the ligand chelates a single ruthenium center of the cluster and can undergo deprotonation concomitant with dearomatization of its naphthyridine core. Although the cluster bearing a partially dearomatized ligand reacts with H2, we found no indication that this proceeds via a pathway involving metal‐ligand cooperativity.
Ru3(μ‐CO)3(CO)5‐type clusters bound to the dinucleating PNNP expanded pincer ligand are described. Deprotonation of a methylene linker of the PNNP ligand gives an anionic triruthenium cluster featuring a dearomatized PNNP ligand. Interestingly, H2 activation by the resulting anionic cluster appears not to proceed through metal‐ligand cooperativity.