Structural diversity in sterically demanding diiminophosphinato alkali metal complexes

We have prepared the new aminophosphine Ph2PNHMes 2 [Mes = mesityl (2,4,6-Me3C6H2)], and the aminoiminophosphorane Ph2P(=NMes)NHMes 4 (MesLH), and obtained the new alkali metal complexes [(DipLLi)2] 5 [DipL = Ph2P(NDip)2, Dip = 2,6-iPr2C6H3], [(MesLLi)2] 6, [(DipL)(DipN2L)Li2] 7 [DipN2L = Ph2P(NDip)(N3Dip)], [(DipN2L)2Li2] 8, [DipLLi(THF)] 9, [DipLLi(THF)2] 10, [(DipLNa)2] 11, [(MesLNa)n] 12, [DipLNa(THF)2] 13, [{MesLNa(THF)}2] 14 and [MesLK] 16 by deprotonation of their respective ligand precursors with standard strong alkali metal bases in various solvents. The crystal structures of 2, 4–6, 7·8, 9–14, and 16 are reported. The different coordination modes in their solid-state structures are discussed and generally compared to the solution behavior of those species