Journal of the American Chemical Society, Vol.136, No.27, 9710-9718, 2014
Method of Continuous Variation: Characterization of Alkali Metal Enolates Using H-1 and F-19 NMR Spectroscopies
The method of continuous variation in conjunction with H-1 and F-19 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.