Substitutions of coordinated salicylaldehyde and its Schiff bases

Summary Several bis/tris-salicylaldehyde, salicylaldimine and salicyalethylenediimine chelates of cobalt(III), chromium(III), cobalt(II), nickel(II) and copper(II) readily react with various brominating agents and undergo α-bromo/cyano/succinimido substitution, with or without accompanying bromine substitution of the aryl ring. The selectivity of these reactions on the metal-coordinated salicylaldehyde derivatives allows the preparation in 50–80% yield of hitherto unreported specific α-bromo products. The substituted organic compounds could be isolated by demetallation of the chelate products.