Structural Diversity of Lithium <i>N</i> ‐Mesityl‐ <i>P</i> , <i>P</i> ‐diphenylphosphinimidate of the type [(L)Li{O−PPh ₂ =N−Mes] _n Depending on Lewis Base L

Metalation of N-mesityl-P,P-diphenylphosphinic amide with nBuLi in toluene yields tetranuclear lithium N-mesityl-P,P-diphenylphosphinimidate ([Ph2P(OLi)=N−Mes]4, 1). Ph2P(O)−N(H)Mes a mixture dibutylmagnesium and butyllithium DME leads to formation dinuclear [Ph2P{OLi(dme)}=N−Mes]2 (2). Excess gives [Li(O−PPh2=N−Mes){Ph2P(=O)−N(H)−Mes}]2 (3) three-coordinate alkali ions. The metathetical approach via reaction 1 anhydrous magnesium bromide ethereal solution [{(thf)LiBr}2{(thf)Li(O−PPh2=NMes)(Et2O)Li(O−PPh2=NMes)}] (4). Heterobimetallic Li/Mg compounds are not accessible by these protocols. Reactions DME, excess or LiBr allows the straightforward conversion 2, 3 4.