In the solid state THF-activation product K[2] also adopts a polymeric structure, in which K + counter ions bridge between the NON-Dipp group and the activated C4H7O moiety of one molecule and the SiPh3 unit of a neighbouring molecule (Figure ). The Al1-N3 distance is 1.871(3) Å, i. For comparison, gallium imide complex K[(NON)Ga{N(SiPh3)}], K [3], was also prepared via the reaction of the analogous potassium gallyl compound K2[(NON)Ga]2 with triphenylsilyl azide. Like its aluminium congener K[1a], K [3] rapidly crystallises as fine needles from benzene, although in this case these are unsuitable for X-ray crystallography. K [3] gives rise to a near identical 1 H NMR spectrum to K[1a], with characteristic resonances at dH = 6.75/6.39 (xanthene aromatic CH) and 3.77/2.94 ppm (Dipp i Pr methine). Unlike K[1a], K [3] is unreactive towards small amounts of THF, and it can be solubilized by reaction with 2.2.2-cryptand to enable the acquisition of C NMR data. Although its molecular structure in the solid state could not be determined crystallographically, the formulation K[(NON)Ga{N(SiPh3)}] is also implied by its onward reactivity (see below).