TY - JOUR
T1 - 178. the use of aprotic solvents for nucleophilic substitution reactions at C(3) and C(17) in steroids
AU - Henbest, H. B.
AU - Jackson, W. R.
PY - 1962/12/1
Y1 - 1962/12/1
N2 - 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%).
AB - 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%).
UR - http://www.scopus.com/inward/record.url?scp=37049045394&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:37049045394
SN - 0368-1769
SP - 954
EP - 959
JO - Journal of the Chemical Society (Resumed)
JF - Journal of the Chemical Society (Resumed)
ER -