Cholestanes containing 3α-substituents (cyano, azido, bromo, fluoro, acetoxy) have been obtained in good yields (>70%) from reactions of cholestan-3β-yl toluene-9-sulphonate with nucleophiles in aprotic solvents. In comparison, reactions of cholestan-3α-yl toluene-p-sulphonate with cyanide and acetate ions gave more elimination, but the 3β-cyanide and 3β-acetate were obtained in 40% and 57% yields, respectively. Use of aprotic solvents inhibits structural rearrangement in nucleophilic replacement reactions at C(17), and good yields of 17α-azido-, -bromo-, -chloro-, and -fluoro-compounds were obtained from testosterone toluene-p-sulphonate. Reaction of this ester with acetate anion in N-methylpyrrolidone gave the 17α-acetate (34%) and 3-oxoandrosta-4,16- diene (57%).
|Number of pages||6|
|Journal||Journal of the Chemical Society (Resumed)|
|Publication status||Published - 1 Dec 1962|