No abstract

Pyrazole-derived polydentate ligands impart substantial stability to organometallic complexes with respect to atmospheric oxidation. In certain complexes, such ligands can also enable the metal to activate and transfer dioxygen. Three classes of ligands have been studied with respect to a series of molybdenum It-allyl complexes to compare the influence of ligands on structure and reactivity. Many of these complexes were stereochemically non-rigid and amenable to DNMR study. A number of interesting and subtle effects have been observed as a result of apparently minor variation on ligand structure or substitution. Structural confirmation was based on X-ray crystal structure analyses of representative complexes.