Syntheses and Fluorescence of Salicylaldimine Schiff Base Derivatives of 1,1′-Di(aminoethylaminocarbonylalkyl)-2,2′-biimidazole

The amide-amine. 1,1'-di(aminoethylaminocarbonylethyl)-2,2'-biimidazole (DAEPB) (1), and subsequent Schiff base imine product, 1,1'-di(salicylaldiminoethylaminocarbonylethyl)-2,2'-biimidazole (DSEB) (2a), have been synthesized from the ester, 1,1'-di(ethoxycarbonylethyl)-2,2'-biimidazole (DEPB). Additionally, 1,1'-di(saticylald iminoethylaminocarbonylinethyl)-2,2'-biimidazole (DSMB) (2b), was prepared from its corresponding amide-amine. All compounds were characterized with FTIR, NMR and elemental analyses. The salicylaldimines, compounds (2a) and (2b), exhibit fluorescence at 540 and 520 nm, respectively, over a broad range of excitation wavelengths.