Totalsynthese von (+)-D-Homoöstron-3-methyläther

✍ Scribed by Jürg Gutzwiller; Werner Meier; Andor Fürst

• Publisher: John Wiley and Sons
• Year: 1977
• Tongue: German
• Weight: 856 KB
• Volume: 60
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/hlca.19770600717

✦ Synopsis

Total Synthesis of (+)‐D‐Homoestrone 3‐methyl ether

A novel total synthesis of (+)‐D‐homoestrone 3‐methyl ether (21) is described starting from (S)‐8a‐methyl‐3,4,8,8a‐tetrahydro‐2__H__, 7__H__‐naphthalene‐1,6‐dione (1) as a chiral synthon for the rings C and D. The key step involves alkylation of the derived 3 with m‐methoxyphenacyl bromide (4) as an AB‐building block to give the dioxo‐secosteroid 5. Hydrogenation of 5 affords the trans‐decalone 11. As by‐products the epimeric cis‐decalones 12 and 13 were characterized. Cyclization of 11 leads under kinetic control predominantly to the Δ^9(11)^‐tetraene 14. Catalytic hydrogenation of 14 and subsequent modification in ring D give the title compound 21. It was found that 14 and also the derived Δ^8^‐isomer 15a add hydrogen from the α‐face of the molecule to an extent of about 80%. The 8α‐D‐homoestrone derivatives 20a and 23 as well as the 9β‐isomers 19a and 22 were characterized.