Highly activated carbonyl groups in linear polycarbonyl compounds can be singled out for study by suppressing the reactivity of adjacent carbonyl groups through the introduction of steric hindrance. Thus the relative inertness of a ketone group attached to a mesityl radical as in dimesityl ketone (I), dimesityl diketone (11) and mesitylglyoxal CV) 2 appears to be equally marked in dimesityl tetraketone (IV), 3
