CHEMICAL STUDIES WITH 11-Oxygenated STEROIDS. I. 17α-Hydroxycorticosterone

meta-Chloroperbenzoic acid (mCPBA): a versatile reagent in organic synthesis

“…A wide variety of synthetic reagents and methods are currently available for the synthesis of a-chloroketones 121 and the large majority of these chlorination methods involve the a-chlorination of ketones, whereas only a few examples of the direct conversion of secondary alcohols into a-chloroketones have been reported. [122][123][124][125] Ryu et al 126 found that secondary benzylic alcohols were easily oxidized concomitantly in situ using the mCPBA-HCl-DMF system to yield a-chloroketones in good yields (Scheme 14). It was found that the reaction initially involved the rapid transformation of the alcohol into a ketone followed by a-chlorination.…”

Organic Hypohalites.

“…Allyl alcohol, which contains a double bond, adds the active reagent, but it is also possible to oxidize it to acrolein under suitable conditions (77). ¿erí-Butyl hypochlorite has recently been used to oxidize a number of steroid alcohols to ketones (16,76,112).…”

Hormones

“…Another cortisol production process, developed by Upjohn [227], starts with pregnane-3α,17α-diol-11,20-dione (104) obtained from progesterone [228]. Here, the 3α-hydroxyl group is oxidized to a 3-keto group with tertbutyl hypochlorite with simultaneous chlorine substitution at position 4.…”