Studies in aluminium soaps-I aluminium tri-soaps

Abstract

It has been found that three moles of isopropanol can be distilled out azeotropically when one mole of aluminium isopropoxide is treated with an excess of fatty acids in benzene. The products, on removal of the excess fatty acids by a suitable solvent such as dioxane or acetone, were in all cases found to be aluminium tri-soaps. Tri-valerate, tri-laurate, tri-myristate, tri-palmitate, and tri-stearate of aluminium have been prepared by this method. The tri-soaps are found to give quite mobile solutions in benzene. The failure of earlier workers to prepare tri-soaps of aluminium has been explained on the basis of the slowness of the final stage of the reaction caused by steric hindrance. It has been shown that there is an exothermic reaction between aluminium isopropoxide and acetic anhydride, but the reaction becomes slow towards the end. However, aluminium tri-acetate can be prepared by refluxing aluminium isopropoxide with an excess of acetic anhydride.