Autocatalytic demetalation of a Zn(salphen) complex provoked by unprotected N-heterocycles

The interaction of Zn(salphen) complex 1a with biologically important structures such as (benz)imidazoles and purine has been studied and revealed in the case of unprotected purine and (benz)imidazole derivatives a demetalated product, whereas for structurally related 1-methyl-(benz)imidazole the formation of 1 : 1 coordination complexes was evidenced by NMR, MS and X-ray crystallography.