Studies on the regioselectivity of the Baeyer-Villiger reaction of 3-keto steroids: conformational effects determine the migration aptitude.
A detailed study of the Baeyer-Villiger reaction of 3-ketosteroids has been performed by using m-chloroperoxybenzoic and trifluoroperoxyacetic acids as oxidants. The process was fully regiospecific for 3-keto-5alpha-steroids with the employ of both peracids, and only partially regioselective for 3-keto-5beta-steroids by using trifluoroperoxyacetic acid. Interestingly, the reaction resulted completely unselective for 3-keto-5beta-steroids by using m-chloroperoxybenzoic acid. Theoretical studies were performed to explain the regiochemistry of this process, which is suggested to be controlled by conformational effects in the transition state of the Criegee rearrangement.
Rivera
Daniel G
DG
Center for Natural Products Study, Faculty of Chemistry, University of Havana, Havana 10400, Cuba. drivera@ipb-halle.de
Pando
Orlando
O
Suardiaz
Reynier
R
Coll
Francisco
F
D015394:Molecular Structure; D010084:Oxidation-Reduction; D013256:Steroids / Q000737:chemistry*
D013256:Steroids