Synthesis and structure of [{MeAl((mu)-PMes)(PMes)}2Li4]2·7thf, containing a [MeAl((mu)-PMes)(PMes)]24– tetraanion (Mes = 2,4,6-Me3C6H2)

The reaction of MeAlCl2 with MesPHLi (1:4 equivalents) in thf/toluene gives the cage complex [{MeAl((mu)-PMes)(PMes)}2Li4] 2·7thf (1), containing an [{MeAl((mu)-PMes)(PMes)}2]4– tetraanion which is valence-isoelectronic with extensively studied Group 15 anions of the type [E((mu)-NR)(NR)]22–