Thermolysis of quinone monoketals la4 at 180" C leads to disproportionation to the p- alkoxyphenols 2a-d and the carbonyl compounds derived from the alcohol moiety of the ketal. The thermolysis of 4, 4-dimeth-oxy-2, 5-cyclohexadienone (la) followed first-order kinetics, and the rate of reaction decreased by a factor of 3.6 when the methoxy groups were replaced with methoxy-d3 groups. The suggested mechanism for the reaction involves ...
