The Transformation of Cyclic Alcohols into Cyclic Acetals through a New Oxygen Atom Insertion by Photolysis in the Presence of Lead Tetraacetate and Iodine
isolated products. Thus, cholesterol gave 4-oxa-A-homocholest-5-en-3-ol and its acetate in a 53% yield. The products differ considerably from those reported by us after the photolysis of the hypoiodites by using mercury(II) oxide and iodine as the reagents for generating the hypoiodites; they also differ from those in the oxidation of the steroidal alcohols with leadtetraacetate alone. The photolysis