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Research areas


Redox-active main group centres

Reversible redox chemistry is generally considered to be the realm of transition metal systems, which contain energetically proximate frontier molecular orbitals. This unique electronic structure can be finely tuned using coordination chemistry, which forms the foundation of modern transition metal catalysis. However, some of the most valuable catalytic transformations also require elements (e.g. Pd, Pt, Rh, Ru, Au) whose prohibitive costs and/or potential toxicity are limiting factors in their utility. Besides a handful of examples, p-block elements are virtually unexplored as platforms for redox catalysis because they usually undergo irreversible oxidation-state changes. To unlock their potential in this area, we seek to discover the fundamental rules governing changes in frontier orbital energies at main group centres as a function of geometry and ligand environment. We will then use this knowledge to design affordable and non-toxic main group systems for cross-coupling catalysis.

See for example: Angew. Chem. Int. Ed., 2019, 58, 7850-7855.

Cinque Terre

Lewis superacids

Strong Lewis acids such as AlCl3 play an essential role as catalysts in industrial and academic chemistry. They are also precursors to weakly coordinating anions that permit the study of highly electrophilic cations. We are interested in the synthesis of new classes of neutral and cationic Lewis superacids (more acidic than SbF5) for fundamental studies involving binding of non-classical donors in main group coordination chemistry (H2, Si-H, N2, COx, NOx, olefins etc.), and for applications in catalysis and anion sensing. Some of these Lewis acids will also be converted to weakly coordinating anions, which are important tools in organometallic chemistry, and may find applications as electrolyte components in batteries. In order to broaden the utility of these compounds, we will devise strategies to make Lewis superacids that can be handled under ambient conditions. This effort will draw upon emerging concepts in Lewis acid chemistry such as steric frustration and cooperative Lewis acidity.

See for example: Chem. Eur. J., 2019, In Press (DOI: 10.1002/chem.201901333).


Inorganic polymers and clusters

Polymers and clusters derived from elements other than carbon are fascinating because their unique electronic structure leads to properties that are in accessible for organic compounds. For example, polysilanes and polystannanes exhibit σ-bond conjugation and act as molecular wires. We are interested in preparing polymers with a backbone derived from the group 15 elements, which would feature a redox active lone pair in the main chain. The fundamental chemistry of such materials is entirely unknown. We are also interested in main group homopolyatomic cations - the positively-charged versions of Zintl anions. More specifically, we will investigate binary or ternary mixtures of well-defined ions as a route to tailor-made molecular clusters of semiconducting intermetallics. These will shed light upon the properties of bulk seminconducting phases and will themselves exhibit interesting reactivity.