Tomasevich Laura L, Collum David B
Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University , Ithaca, New York 14853-1301, United States.
J Am Chem Soc. 2014 Jul 9;136(27):9710-8. doi: 10.1021/ja504365z. Epub 2014 Jun 25.
The method of continuous variation in conjunction with (1)H and (19)F 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.
采用连续变化法结合¹H和¹⁹F核磁共振光谱对由N,N,N',N'-四甲基乙二胺(TMEDA)和四氢呋喃(THF)溶剂化的锂烯醇盐和钠烯醇盐进行表征。然后将一种利用锂烯醇盐开发的策略应用于更具挑战性的钠烯醇盐。许多由TMEDA或THF溶剂化的钠烯醇盐仅生成四聚体。有证据表明,TMEDA在立方四聚体上螯合钠。