 Solution

Stoichiometry gives H = $\mathrm{Ph}(\mathrm{TMP}{)}_3\mathrm{CuL}{\mathrm{i}}_3$, formally F plus two LiTMP units. A compatible ring connectivity is $\mathrm{Ph}-\mathrm{Cu}-{\mathrm{N}}_1-\mathrm{Li}-{\mathrm{N}}_2-\mathrm{Li}-{\mathrm{N}}_3-\mathrm{Li}$, closed through a lithium–phenyl interaction. The TMP attached to copper, N${}_1$, remains chemically distinct; N${}_2$ and N${}_3$ belong to the more labile lithium-amide part.

Reversible detachment and reattachment of a symmetric $(\mathrm{LiTMP}{)}_2$ segment can exchange its two amides and reassign which Li occupies the phenyl-contacting or nitrogen-bridging positions. It can therefore exchange all three Li sites and the two Li-associated TMP groups while retaining the Cu-bound TMP group. Fast TMP-ring conformational inversion can further average methyl environments without exchanging entire ligands. These are different kinds of motion; simple ring inversion alone cannot explain exchange of the lithium sites. Such a dissociative interpretation is consistent with the experimentally studied lithium-rich aggregate, but the exchange pattern does not determine a unique transition state or prove that every bond breaks in one concerted event.