Synthetic, structural and magnetic implications of introducing 2,2'-dipyridylamide to sodium-ferrate complexes.

Using a transamination approach to access novel Fe(ii) complexes, this study presents the synthesis, X-ray crystallographic and magnetic characterisation of a series of new iron complexes containing the multifunctional 2,2-dipyridylamide (DPA) ligand using iron bis(amide) [{Fe(HMDS)}] and sodium ferrate [{NaFe(HMDS)}] (1) as precursors (HMDS = 1,1,1,3,3,3-hexamethyldisilazide). Reactions of DPA(H) with 1 show exceptionally good stoichiometric control, allowing access to heteroleptic [(THF)·NaFe(DPA)(HMDS)] (3) and homoleptic [{THF·NaFe(DPA)}] (4) by using 1 and 3 equivalents of DPA(H), respectively. Linking this methodology and co-complexation, which is a more widely used approach to prepare heterobimetallic complexes, 3 can also be prepared by combining NaHMDS with heteroleptic [{Fe(DPA)(HMDS)}] (2).