Synthesis and Structure of [{Na(tmeda)}3][LiPh4], an Organometallic Complex Containing Two Different Alkali Metals

The title complex 1 may be described as a pseudo-tetrahedral anion, [LiPh4]3⊖, surrounded by [Na(tmeda)]⊕ counterions. The Na atoms form a nearly equilateral triangle in the middle of which is the Li atom, displaced only slightly from the Na3 plane. Organometallic compounds of lithium and sodium were described in the 1950s by Wittig et al. However, structural characterization has been lacking so far.