With the solid-state structures of the LMg 2 Cl 2 complexes determined, a comparison of the structural features and the bond metrics is possible. The most striking difference between the two complexes is the geometry around the Mg centres (Figure ), being octahedral in 3 and trigonal bipyramidal in 4. We ascribe this change in geometry to the imidate binding mode of the dipp NDC ligand in 3, which results in a decrease of steric bulk around the Mg centres (for a quantification of the steric bulk in both complexes see below). The decreased steric encumbrance allows for the binding of an additional THF molecule and implies that the Mg centres in 4 are coordinatively unsaturated. The increased steric and electronic saturation in 3 results in longer Mg-Cl bonds compared to the same bonds found for 4 (2.460(2)-2.506(3) Å in 3 vs. 2.4089(16)-2.4367(15) Å in 4). The binding of an additional THF molecule in 3 also has a significant influence on the Mg•••Mg distance. This distance in 3 is significantly larger than the distance in 4 (3.428(3) Å vs. 3.084(2) Å respectively). This is due to one of the Mg centres in 3 being pushed outside of the naphthyridine plane and one slightly below the naphthyridine plane (as is evident from their respective torsion angles χ[O1,C1,C2,N1]= -10.6(8)° and χ[O2,C10,C9,N2]= -2.7(8)°, see ESI Figure ) to minimise the distortion of the octahedral geometry. The distance of Mg1 to the least-squares plane of the naphthyridine ring is -0.897(2) Å and the corresponding distance for Mg2 is 0.495(2) Å. Contrastingly, the Mg centres in 4 reside in the naphthyridine plane, with the distance of Mg1 to the leastsquares plane of the naphthyridine ring being 0.0799 (10). Å To quantify the steric environments surrounding the Mg 2 cores in 3 and 4 imposed by each of the ligands, we used the SambVca 2.1 web application to build their respective steric maps. For dinuclear systems, choosing the centroid and radius of the defined sphere for the buried volume calculations is non-trivial, and based on previous work from our group we placed the centroid of the sphere in between the metal centres and set the radius of the defined sphere to 5 Å. The steric maps in Figure reveal that the largest difference in steric encumbrance in the reaction hemisphere of the two complexes is in the cis ligand void space (i.e. above and below the naphthyridine plane). In the case of 4, the i-Pr moieties on the dipp substituents shield the Mg centres above and below the naphthyridine plane, preventing the coordination of additional THF molecules. In the case of 3, the dipp substituents are oriented away from the Mg centres, which significantly decreases the shielding of the cis void spaces by the i-Pr groups. The difference in the steric properties of the ligands in 3 and 4 are also expressed in their respective buried volumes (V bur ) of 27.3% and 35.4%. We envision that these pronounced differences in steric profiles between the two complexes can lead to diverging reactivity due to the varying accessibility of the Mg centres for substrates. The discrepancy in deprotonation order observed for 1 and 4, along with the relative acidity of the methylene protons, prompted us to investigate whether treating dipp DAMN with two equiv of a dialkyl-magnesium species would result in deprotonation and subsequent dearomatisation of the ligand, similar to what is observed for the related t-Bu PNNP ligand when treated with strong bases. Treating a THF solution of dipp DAMN with 2 equiv of Mg(n-Bu) 2 (Scheme 6) resulted in clean formation of 5 as a brown solid in quantitative yield.