Enantioselective reactions are the cornerstone of modern synthetic organic chemistry and are crucial to obtaining enantiopure molecules. Asymmetric catalysis commonly employs catalytic coordination complexes composed of a transition metal surrounded by chiral ligands. BINOL ([1,1'-binaphthalene]-2,2'-diol) and its derivatives are arguably the most popular chelates and have been critical for the development of a wide range of asymmetric catalytic reactions. The utility and effectiveness of these reactions depends on obtaining enantiopure BINOL. One potential method for enriching BINOL involves synthesizing BINOL derivatives with chiral auxiliary groups and using excited state proton transfer to reduce the barrier of rotation between R- and S-BINOL enantiomers. Differences in the energies of these enantiomers will determine equilibrium concentrations and enantiomeric enhancements (ee). In this work, we report excited state time-dependent density functional theory (TD-DFT) energies of R- and S- enantiomers of a series of BINOL derivatives and compare resulting ee values with preliminary experimental work. The future aim of the work is use TD-DFT to predict derivatives with increased ee values.

TD-DFT study of enantioenrichment of BINOL derivatives

2019 Spring National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.