Substitutions of coordinated salicylaldehyde and its Schiff bases

Abstract

Several bis/tris-salicylaldehyde, salicylaldimine and salicyalethylenediimine chelates of cobalt(III), ehromium(III), cobalt(IX), nickel(II) and copper(II) readily react with various brominating agents and undergo a-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 a-bromo products. The substituted organic compounds could be isolated by demetallation of the chelate products.

<B>SYNTHESIS, SPECTRAL AND THERMAL PROPERTIES OF SOME HIGH COORDINATED COMPLEXES OF THORIUM(IV) AND DIOXOURANIUM(VI) DERIVED FROM 4[N-(2\'-HYDROXY-1\'-NAPHTHALIDENE)AMINO] ANTIPYRINETHIOSEMICARBAZONE</B>

“…The absorptions at 1600 cm -1 in the free ligand can be attributed to (C=N) stretching vibrations of imine which is in agreement with the observations of previous workers [23,24]. On complexation this frequency observed to be shifted to lower wavenumber (Table 2).…”