Control and Prediction of Eliminative Cyclization
Dinga Wonanke, Final PhD Seminar, Supervisor: Dr Deborah Crittenden
Time & Place
Mon, 07 Jan 2019 11:00:00 NZDT in Room 701, Level 7, West
All are welcome
Eliminative cyclization reactions provide a versatile synthetic route to functionalized and substituted polyaromatic and heteroaromatic compounds, which form the building blocks of molecular electronics such as organic photovoltaics and organic light-emitting diodes.
These reactions may be either thermally or photochemically driven, and proceed via two steps: planarization to form a stable proto-aromatic intermediate, and elimination of the groups adjacent to the forming bond to yield the final fully aromatic product. Although experimental studies have been performed on a wide range of starting materials to characterize reaction mechanisms and product distributions, there remains no predictive model for determining the outcome of cyclization reactions for any given reactant under specified reaction conditions.
In my PhD, I have investigated the factors that control both the thermodynamics and kinetics of these reactions by explicitly mapping out reaction coordinate profiles for a diverse range of molecules. In this talk, I will explain how eliminative cyclization reactions can be controlled from varying the nature and positions of heteroatoms in different reactant molecular scaffolds, and the influence of reaction conditions on both thermal and photochemical processes. In addition, I will also present the rationale and application of a novel photo-planarization reactivity predictor, which is both computationally efficient and easy to apply. We envisage that this will become a useful synthetic planning tool for pre-identifying candidate molecules likely to undergo eliminative photocyclization.