and LiHMDS and purified by distillation, according to established procedures. Reacting (4-azido-4-methylpentyl)-benzene (1a) with 1 mol% Fe(HMDS)2 in C6D6 at 100 °C resulted in formation of 2,2-dimethyl-5-phenylpyrrolidine (1b) as aminated product in 48% yield after 4 h (Table , entry 1). The conversion was slightly higher (56%) due to the formation of some cyclic imine as the most prominent side product together with small quantities of several other unidentified species. Performing the reaction in toluene-d8 resulted in comparable yields and conversions after 4 h (Entry 2). Notably, THF-d8 significantly inhibited the catalytic activity and even after 24 h, yields did not exceed 38% (Entry 3). We attribute the slow conversion to active site inhibition due to the coordinating ability of THF. Similar effects were observed with other under-ligated complexes. Increasing the temperature to 120 °C resulted in an increase of conversion (70%) and yield (58% after 4 h). To achieve full conversion, 24 h were required, as the reaction slows down in presence of product (vide infra). Accordingly, an increase of catalyst loading to 2% further enhanced both conversion (82%) and yield (74%) within 4 h. The same trend was observed when utilizing 10 mol% catalyst loading, reaching full conversion in only 1 h. However, under these conditions the selectivity is significantly reduced to 62%. Lowering the catalyst loading to 0.1% resulted in a maximum yield of 18% after 4 d (Entry 6). This performance, corresponds to 180 turnovers, making Fe(HMDS)2 despite the simple ligand design one of the more robust iron catalysts known to date,. <sup>20,24,25,30,31</sup><sup>20,24,25,30,31</sup><sup>20,24,25,30,31</sup>Moreover , no Boc2O or other protecting groups were used during the catalysis, which is usually required for other iron systems. In fact, addition of Boc2O is deleterious and completely inhibits catalytic turnover. Notably, the reaction also proceeded at room temperature; at 1 mol% of catalyst in toluene-d8 43% yield and 52% conversion were accomplished after 14 d (Entry 7).