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Biomimetic Platinum-Promoted Polyene Polycyclizations: Influence of Alkene Substitution and Pre-cyclization Conformations.

ABSTRACT: 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.

SUBMITTER: McCulley CH

PROVIDER: S-EPMC5699452 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Biomimetic Platinum-Promoted Polyene Polycyclizations: Influence of Alkene Substitution and Pre-cyclization Conformations.

McCulley Christina H CH Geier Michael J MJ Hudson Brandi M BM Gagné Michel R MR Tantillo Dean J DJ

Journal of the American Chemical Society 20170803 32

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, includi ...[more]

PMID: 28719198

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