Infrared spectra of N,N′-bis(salicylidene)-1,1-(dimethyl)ethylenediamine and its metal complexes

I.R. spectra in the region 4000-400 cm−1 have been recorded for N,N′-bis(salicylidene)-1,1-(dimethyl)ethylenediamine(Sal2-i-bn) and its complexes with divalent nickel, cobalt, copper and palladium. Assignments of the observed frequencies have been made to specific group vibrations by comparison with the spectra of related compounds. Effect of chelation on the ligand group frequencies and the stability order of the chelates are also discussed.