Collect. Czech. Chem. Commun. 1991, 56, 984-990

The oxidation of progesterone under GoAggIII conditions

Derek H. R. Barton and Dario Doller

Department of Chemistry, Texas A and M University, College Station, TX 77843, U.S.A.


The oxidation of pregn-4-ene-3,20-dione (progesterone) by the GoAggIII system (aqueous hydrogen peroxide, ferric chloride, picolinic acid in pyridine-acetic acid solution) has been investigated. Two tri-keto derivatives were isolated and identified as pregn-4-ene-3,6,20-trione and pregn-4-ene-3,12,20-trione. The third major product isolated was identified as the unstable 5α-formyl-A-nor-pregnane-3,20-dione, which deformylated spontaneously to A-nor-5β-pregnane-3,20-dione. A mechanism for the A-ring contraction is proposed, based upon the participation of a carbon-Fe(V) intermediate.