Reaction of androst-5-en-17-one with hypobromous acid and its use for synthesis of 19-oxygenated 5-ene and 4-en-6-one steroids.
Reaction of androst-5-en-17-one (1) with hypobromous acid using a short reaction time (30 min) along with a careful isolation procedure gave, for the first time, the addition product, 5 alpha-bromo-6 beta-hydroxyandrostan-17-one (3), in 43% yield. This bromohydrin was much more reactive than 5 alpha-bromo-3 beta-acetoxy-6 beta-hydroxyandrostan-17-one (4) towards KHCO3 and HClO4. The high reactivity of compound 3 was found to be a principal reason for the difficulty in isolating this compound by the addition reaction so far. 19-Hydroxyandrost-5-en-17-one (16) and androst-5-ene-17,19-dione (18), as well as 19-hydroxyandrost-4-ene-6,17-dione (28) and androst-4-ene-6,17,19-trione (29), were synthesized through hypoiodite reaction of the bromohydrin 3 as a key reaction.
Numazawa
M
M
Tohoku College of Pharmacy, Sendai, Japan.
Yamada
K
K
D000438:Alcohols / Q000737:chemistry; D000735:Androstenedione / Q000031:analogs & derivatives; D000736:Androstenes / Q000138:chemical synthesis; D000737:Androstenols / Q000138:chemical synthesis*; D001959:Bromates / Q000737:chemistry*; D003687:Dehydroepiandrosterone / Q000031:analogs & derivatives* / Q000737:chemistry; D017613:Iodine Compounds / Q000737:chemistry; D007700:Kinetics; D013256:Steroids / Q000138:chemical synthesis*
C111511:19-hydroxyandrost-5-en-17-one; D000438:Alcohols; D000736:Androstenes; D000737:Androstenols; D001959:Bromates; D017613:Iodine Compounds; D013256:Steroids; C111512:androst-4-ene-6,17,19-trione; C023963:bromohydrins; C081961:hypoiodous acid; D000735:Androstenedione; D003687:Dehydroepiandrosterone; C097404:androst-5-en-17-one; C011482:19-hydroxy-4-androstene-3,17-dione; C027664:hypobromous acid