Master of Science
Molecular oxygen (O2) represents the most ideal "green" oxidant for the large-scale oxidation of organic compounds, due to its inexpensive and environmentally benign characteristics. However, a number of challenges remain for its use in the fine chemical and pharmaceutical industry, including the development of highly selective catalytic transformations. NiCl(allyl)(NHC) complexes have been shown to react with O2 to promote the oxidation of the allylic ligand, however non-catalytically.
This report details the synthesis and characterization of novel NiCl(cinnamyl/allyl)(NHC) complexes, containing a pendent 2° amine arm on the NHC ligand to act as a hydrogen-bond donor group. The complexes prove to exhibit dynamic behavior, with the pendent amine showing the ability for hydrogen-bonding and/or hemi-labile ligand coordination to the metal. Dioxygen reactivity studies indicate that the complexes are active for aerobic oxidation, and that the product distribution is different than that of previously reported systems. However, the observed reactivity currently is non-catalytic.
Hazlehurst, Richard J., "Aerobic Oxidations Mediated by Allylnickel(N-Heterocyclic Carbene)Chloride Complexes: Investigating the Role of a Pendent Amine Group" (2016). Electronic Thesis and Dissertation Repository. 3492.