Method of continuous variation: Characterization of alkali metal enolates using 1h and 19F NMR spectroscopies

Abstract

The method of continuous variation in conjunction with 1H and 19F NMR spectroscopies was used to characterize lithium and sodium enolates solvated by N,N,N,N-tetramethylethyldiamine (TMEDA) and tetrahydrofuran (THF). A strategy developed using lithium enolates was then applied to the more challenging sodium enolates. A number of sodium enolates solvated by TMEDA or THF afford exclusively tetramers. Evidence suggests that TMEDA chelates sodium on cubic tetramers. © 2014 American Chemical Society.