Radical Oxidation of 17-Functionalized 14α-Hydroxy Steroids

Abstract

The radical oxidation of 14α-hydroxy steroids with various functional groups at C-17 was studied. Lead tetraacetate and ceric ammonium nitrate were used as oxidizing agents. It was shown that reactions of this type afforded complex mixtures of compounds. However, the radical oxidation of 14α-hydroxy-17-oxo steroid (lead tetraacetate version of the hypoiodite reaction) proceeded smoothly with formation of the 13,14-secosteroid in up to 85% yield. The structure and conformation of the formed 13α-iodo-3α,5-cyclo-13,14-seco-5α-androst-5-ene-14,17-dione was determined by X-ray analysis.

Synthesis and radical oxidation of steroidal 1-oxo-5α-alcohols

“…Their oxidation proceeded smoothly, resulting in a good yield of iododiketones, which are convenient intermediates for further modifications. 10 This approach was successfully used to prepare a number of androstane 13,14-seco steroids. 11,12 The main idea of the present investigation, which aimed to develop new synthetic approaches to 5,10-seco steroids, was to examine the influence of a carbonyl group at C-1 (in β-position to hydroxyl group at C-5) on the course of radical oxidation.…”

“…The general procedure for the radical oxidation of 12 was similar to that described in earlier papers. 10,19 The reaction was carried out in refluxing benzene using a 1.5 mol excess of lead tetraacetate with the presence of iodine as a catalyst and calcium carbonate as a base. Although it resulted in the formation of a complex mixture of products, compound 13 could be isolated in a reasonable 56% yield.…”

Oximes of Seven-Membered Heterocyclic Compounds Containing One Heteroatom

“…Radical oxidation of the steroid derivative 45 with lead tetraacetate in the presence of calcium carbonate and iodine leads to formation of a mixture of О-methyloxime 46 and macrocyclic compound 47[50].…”