Facile Baeyer-Villiger oxidation of cyclic ketones: Conventional versus microwave-assisted approach

The Baeyer-Villiger oxidation of cyclic ketones (I) to the corresponding lactones (II) can be improved using m-CPBA under microwave dielectric heating. A dramatic reduction of time - 3 min compared to 5 days at room temperature - was observed to transform cycloheptanone into oxocan-2-one. Ω-Hydroxyalkyl hydroxamic acids (III), key intermediates for a rapid access to potent histone deacetylase inhibitors, are obtained in one-pot reaction of lactones using the Weinreb amidation.