ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
In a search for a new and efficient synthesis of the compound 7, the cyclization of 5 (obtained by a Michael-reaction from 3 and 4) was studied. Treatment of 5 with strong acid furnished the known dienedione 8. Mild acidic conditions gave the bridged alcohol 9 and other, unidentified products, rather than the desired enone 6. Under basic conditions, 5 did not cyclize to 6, but underwent retro-Michael reaction. Attempts were then made to convert the dienedione 8 to the 14α-enone 19. However, both catalytic hydrogenation and lithium-ammonia reduction of 8 yielded mainly 14β-products. In some hydrogenation experiments, isomerization of the dienedione 8 to the phenols 13 (major) and 14 (minor) occurred. The stereochemistry of the new isomeric des-A-androst-9-en-5, 17-diones (16, 17 and 20) was determined by chemical and spectroscopic methods.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19700530512
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