Optical Rotatory Dispersion Studies. CVII.¹ Factors Governing the Relative Stability of Hydrindanones. Syntheses of 17-Alkyl-15-keto Steroids²

Stereoselective routes to 14,15,17-trisubstituted-3-methoxyestra-1,3,5(10)-trienes

“…Direct oxidation of the 15p-phenylseleno-l4r,l7@-diol (21) with Jones reagent afforded a compound taken to be the 14a-hydroxy-Al5-17-ketone (25). rearrangement of @,y-epoxy-ketones; thus, the 14c(,15aepoxy-17-ketone (24), obtained through Corey oxidation of the corresponding alcohol (17), was quantitatively converted, during exposure to silica gel, into the identical product (25). Furthermore, catalytic hydrogenation of (25) furnished the known 2o 14a-hydroxy-17-ketone (27), which was also prepared more directly from the 14cr,15aepoxy-17P-acetate (19), through successive reductive cleavage with lithium aluminium hydride arid Jones oxidation of the intermediate 14~,17p-diol (26).…”

“…14,15a-Epoxy-3-methoxy-14a-estra-1,3,5( lO)-trien-17-one (24).-Dimethyl sulphide (100 pl) was added to a solution of N-chlorosuccinimide (135 mg) in toluene (5 ml) a t 0 "C under nitrogen. The resulting suspension was cooled to -25 "C and the 17-alcohol( 17) (205 mg) in toluene ( 10 ml) was added dropwise.…”

Efficient Stereocontrolled Access to 15- and 16-Hydroxy Steroids

“…It is known that the direction of hydrogen attack on a ∆ 16 double bond is dependent of alternative reducing reagents (Superhydride ® , DIBAL-H), but no improvements were observed. on the configuration at C-14: [32] A 14α configuration leads to α-face hydrogenation, whereas the 14β isomer is satuAttention was then turned to the ∆ 15 steroid 10 once more. In order to introduce the oxygen function at C-15, rated from the β side.…”

Efficient Stereocontrolled Access to 15- and 16-Hydroxy Steroids

“…on the configuration at C-14: [32] A 14α configuration leads to α-face hydrogenation, whereas the 14β isomer is satu-Attention was then turned to the ∆ 15 steroid 10 once more. In order to introduce the oxygen function at C-15, rated from the β side.…”