Structurally diverse pyridyl or quinolyl enolato/enamido metal complexes of Li, Zr, Fe, Co, Ni, Cu and Zn

•Modular synthesis of pyridyl and quinolyl enolato and enamido ligands.•Simple κ2 and unusual η5 coordination modes.•Monomeric to trimeric cage assemblies.•Oxido-bridged bimetallic and oxido-centered trimetallic clusters.

Simple β-ketiminates and β-diketiminates are important monoanionic [N,O] and [N,N] chelating ligand systems with a rich coordination chemistry across the periodic table of elements. New structurally related ligands having one imine donor annelated by an heteroaromatic ring system were easily accessible by reacting α-picolyl/quinolyl-lithium with nitriles followed by sequential acidic hydrolysis and condensation with primary aromatic amines. The coordination chemistry of these [N,O] and [N,N] ligands was fully explored with metals ranging from group 1 to group 12 (M = Li–Zn) resulting in a large variety of coordination modes, including common k2 and rare h5 motifs as well as novel oxido and non-oxido-bridged cluster assemblies, as shown by a total of 19 single crystal structure analyses.

Graphical abstractPyridyl/quinolyl-annelated enolates or enamides are easily accessible by a modular synthesis starting from α-picoline or quinoline. Their coordination chemistry is surprisingly rich, as evidenced by X-ray single structure analyses of simple [N,O]/[N,N]nM monomeric complexes, higher nuclearity assemblies with or without incorporated oxido ligands, and unusual π-complexes.Figure optionsDownload full-size imageDownload as PowerPoint slide