Isomerization of Cyclohexyl Phenyl Ketoxirne in Liquid Sulfur Dioxide

Abstract 1. The syn-anti isomerization of β-cyclohexyl phenyl ketoxime is carried out in liquid sulfur dioxide. 2. The isomerization is accerelated by light and retarded by hydroquinone. The degree of the dehydration of liquid sulfur dioxide has little effect on the rate of isomerization. 3. The kinetic result has shown that the reaction is of the first order with respect to the concentration of the oxime and that the rate constant, k for R=k[β-oxime], may be expressed as: k=6.3×1011 exp [−19.1⁄RT] 4. A complex between the oxime and sulfur dioxide is assumed as the intermediate step, the isomerization of the complex being the rate-determining step. The dual (radical and ionic) nature of the isomerization in liquid sulfur dioxide may well be elucidated by such an assumption.