OR' ( a ) , R = CH3, R1 = H (b), R = CH3, R1 = COCH3 (c)> R = CH3, R1 = Tetrahydropyran-2-yl ( e ) , R = C2H5, R1 = COCH3 i f ) , R = C2H5, R1 = Tetrahydropyran-2-yl (d), R = C2H5, R' = H 190-In spite of numerous experiments directed toward this aim 131, no simple and productive technique has hitherto been found.For our investigations we chose the route ( I ) +(5) via the 5.1Op-methylene steroids (4) [41. For the success of this pathway it was essential t o reduce 3-oxo-5(10)-estrenes ( I ) (which are readily obtainable by Birch reduction and subsequent enolether cleavage of steroids having an aromatic ring A) stereospecifically to 3P-hydroxy-5(10)-estrenes (2). This reduction gives only 15-20% yields when carried out with complex metal hydrides, hydrogen in the presence of a platinum catalyst, or according t o the Meerwein-Ponndorf method; the main products are 3cr-hydroxy-5(1O)-estrenes [4C, 51. A total yield of only about 30% is also obtained in the conversion of ( I ) into (2) by epimerization of 3a-hydroxy-5(10)-estrenes [5aJ or via 5,l Op-epoxy steroids [4cl.We have now found that 3-oxo-5 (10)-estrenes ( l a ) -( I f ) [IR: v = 1710 cm-1 (C=O), NMRI6J: 6 = 2.45 (intensity = 4, WI/, = 4 Hz) (H-1 and H-2). 2.75 (intensity = 2, W I / , = 5 Hz) (H-4)] 171 can be converted into the corresponding 3phydroxy compounds (2a)-(Zf) [NMR: 6 = 3.90-4.20 (H-3); with (2c) and ( 2 f ) this signal partly overlaps with that of the O C H 2 group of the tetrahydropyranyl ether] 171 in 65-90% yield by catalytic hydrogenation if highly active Raney nickel is used as catalyst and the reaction is performed under a hydrogen pressure as close t o 200 atm as possible. Compounds (Zb), ( 2 c ) , (Zej, and ( 2 f ) can, according to Simmons-Smith [*I, be converted into the 5$,19-cycloandrostanes (36). (3~). (3e). and (3f), respectively [IR: v = 3050 cm-1 (cyclopropane), N M R : 6 = 0.40 (cyclopropane)] in yields of up to 90% by refluxing with diiodomethane and zinc-copper couple [91 in ether/l,2-dimethoxyethane for 2 h. Jones oxidation[lol of the products with chromic acid in acetone smoothly affords the 3-ketones (46). (4c), (4e), and (4f) [IR: v = 1705 cm-1 (C=O), 3050 cm-1 (cyclopropane), N M R : 8 = 0.48 (cyclopropane), 2.52 (singlet, intensity = 2) (H-4)] [7J, which are isomerized o n treatment with concentrated hydrochloric acid in glacial acetic acid (2:3) for 10 min at 70 "C [3b, 3C,4CI. Mixtures of 17p-hydroxy and 17F-acetoxy steroids may then be isolated which can be hydrolyzed to the testosterones (5a) or (5d), or acetylated t o the testosterone acetates (5b) or (5e) [UV: €240 = 16500; IR: v = 1670 cm-1 (C=O), 1615cm-1 (C-C); NMR: 6 = 1.20 (CH3-10), 5.70 (H-4)] ["I. The yield of the reaction (4) +(5) again amounts to up t o 90%.