The clean access to 2 as a rare base-free, room-temperature stable and highly soluble divalent lanthanide complex gave us the opportunity to study its reactivity towards industrially relevant small molecules, such as H2, which usually does not bind strongly with f-elements. Herein, its coordination to the lanthanide center in 2 would not suffer from the presence of a better ligand. Due to its unique properties, 2 reacts with H2 under very smooth conditions (1.2-1.5 bar of H2, ambient temperature), leading to quantitative conversion into the hydride complex 3-H over the course of 1-3 days (Figure ). Reaction with D2 proceeded similarly, yielding the Lu III deuteride 3-D, without any appreciable deuteration of the ligand backbone. It should be stressed that the reactivity of 2 with H2 is much faster than its thermal decomposition into 3-H and 4 (see Figure ), meaning that another direct pathway must be active to form 3-H (see below for mechanistic insights by DFT calculations).