Kinetic stabilisation of a molecular strontium hydride complex using an extremely bulky amidinate ligand

Two extremely bulky amidinate ligands, [RC{N(Dip)}{N(Ar^†)}]⁻ (Dip = 2,6-diisopropylphenyl; Ar^† = C₆H₂{C(H)Ph₂}₂Prⁱ-2,6,4; R = 1-adamantyl (L^Ad), tert-butyl (L^tBu)) have been developed and utilised for the kinetic stabilisation of the strontium and magnesium hydride complexes, [L^AdSr(μ-H)]₂ and [L^RMg(μ-H)]₂ (R = Ad or Bu^t). The former represents the missing link in the series of dimeric systems, [LAe(μ-H)]₂ (Ae = alkaline earth metal). The structure and bonding of the complexes have been studied by crystallographic, spectroscopic and computational techniques.