Stabilization of unsolvated europium and ytterbium pentafluorophenyls by pi-bonding encapsulation through a sterically crowded triazenido ligand.

The one-pot transmetalation/deprotonation reaction of the bulky triazene Dmp(Tph)N3H with bis(pentafluorophenyl)mercury and europium or ytterbium affords the structurally characterized unsolvated metal(II) pentafluorophenyl triazenides [Dmp(Tph)N3MC6F5] (M = Eu, Yb; Dmp = 2,6-Mes2C6H3 with Mes = 2,4,6-Me3C6H2; Tph = 2-TripC6H4 with Trip = 2,4,6-(i)Pr3C6H2) or, depending on the molar ratio, the solvated complex [Dmp(Tph)N3YbC6F5(THF)].