The stability of the Mg-Mg bond needed to be dealt with. Researchers began to investigate sterically demanding guanidinates and amidinates. Their stabilizing abilities in low-oxidation state chemistry was attractive since it allowed for other low-valent main group complexes to be achieved. This research also allowed for the first stable dimer Mg(I) dimer, [{(Priso)Mg}]. Potassium reduction of heteroleptic Mg(II) iodide precursor complexes were then carried out. The ligands guanidinato and, β-diketiminato Mg(II) iodide etherate complexes can be prepared from free NH ligands and methyl magnesium iodide in diethyl ether. An example of the synthesis of the precursor synthesis can be shown below. An additional precursor synthesis is shown, needed for [{(Nacnac)Mg}], which can be explained in the section below.