Formation of 1 : 1 complexes of ferrocene-containing salen ligands with Mg, Ti and Zr

Condensation of 1,1'-diaminoferrocene with a range of salicylaldehydes resulted in the formation of the corresponding salen-type ligands in high yields. The ability of these compounds to serve as ligands was demonstrated by the formation of several 1 : 1 Zr and Ti complexes, one of which was structurally characterized and was found to feature a (t-Bu)Salfen(2-) ligand in a square-planar conformation. In addition, a related Schiff-base ligand was synthesized by condensing diaminoferrocene with 2,4-petanedione and a Zr complex of this ligand was isolated.