Notably, with NacNac ligands there is a degree of mechanistic flexibility in the dehydrocoupling step due to the possibility of direct protonation of the M-H/M-Me unit or ligand non-innocence (backbone protonation) mediating subsequent dehydrocoupling. Computational analysis of both pathways revealed the lowest energy route is predominantly dictated by (i) the accessibility of the amine-free [NacNacM] + complex and (ii) the degree of stericderived distortion towards a boat conformer upon backbone protonation. For example, with the aluminum system an amine-free cation ([NacNacAlMe] + ) is energetically accessible enabling protonolysis to proceed in a separate step to Alamine bond formation. However, for the zinc system no amine-free cation ([NacNacZn] + ) is energetically accessible, precluding a stepwise Zn-H protonation-amine binding process, resulting in an alternative mechanism that proceeds via ligand non-innocence. With other ligands backbone protonation may not be feasible therefore careful selection of the organometallic complex is essential to avoid high energy intermediates/barriers during dehydrocoupling that would therefore preclude catalytic C-H metalation. Based on the insights afforded from this initial study, and the fact it is applicable to two disparate metals (Zn and Al) we believe that multiple other main group metals and other ligand sets will be amenable to this transition metal-free, catalytic in base, C-H metalation approach. Thus, it has the potential to facilitate the synthesis of a range of important organometallic reagents.