Baeyer-Villiger Oxidation of Functionalized Ketones

Because of the common mechanisms and the same specific oxidants, the Baeyer-Villiger oxidation of ketones possessing other functional groups will be mentioned in this section rather than in the places where it should be discussed according to the system of the book. 

The results of oxidation of unsaturated ketones depend on the position of the double bond with respect to the carbonyl group and on the oxidant. 

An example showing the behavior of a ketone containing a noncon-jugated double bond is the oxidation of 2-allylcyclohexanone. Hydrogen peroxide in benzonitrile produces exclusively an epoxide [148, whereas peroxyacetic acid 148 or bis(trimethylsilyl) peroxide [237 yields the lactone of 6-hydroxy-8-nonenoic acid (equation 388). 

Most of the discussion of the Baeyer-Villiger reaction of unsaturated ketones is devoted to a,(3-unsaturated ketones, such as mesityl oxide [254], benzalacetophenone [307, and, especially, benzalacetone [25S], The oxidation of ionones does not involve the Baeyer-Villiger reaction and is, therefore, discussed elsewhere (see equations 440 and 441). 

The treatment of mesityl oxide with 45% peroxyacetic acid in chloroform at 20-25 °C for 4.5 h gives a 53% yield of a mixture containing 22% of 4-methyl-3,4-epoxypentan-2-one and 78% of 2-acetoxy-3,3-di-methyloxirane (the combined products of epoxidation and the Baeyer-Villiger reaction) (equation 389) [254.  

---