Biomimetic Platinum-Promoted Polyene Polycyclizations: Influence of Alkene Substitution and Pre-cyclization Conformations
figureposted on 2017-07-18, 00:00 authored by Christina H. McCulley, Michael J. Geier, Brandi M. Hudson, Michel R. Gagné, Dean J. Tantillo
Results of kinetic experiments and quantum chemical computations on a series of platinum-promoted polycyclization reactions are described. Analyses of these results reveal a reactivity model that reaches beyond the energetics of the cascade itself, incorporating an ensemble of pre-cyclization conformations of the platinum–alkene reactant complex, only a subset of which are productive for bi- (or larger) cyclization and lead to products. Similarities and differences between this scenario, including reaction coordinates for polycyclization, for platinum- and enzyme-promoted polycyclization reactions are highlighted.