A tetraethylene pentamine-diamine (L4), the biggest compound in the family of dibenzylated diimine-polyamines (L1–L4) has been synthesized by classical Schiff-base reaction between benzaldehyde and the diamine tetraethylenepentamine, and the structure was confirmed by elemental analysis, ESI-MS spectrometry and by IR and 1H-NMR spectroscopy.