ISSN:
0009-2940
Keywords:
3-Azabicyclo[3.3.1]nonanes
;
1-Azaadamantane derivatives
;
Clemmensen reduction
;
Dichlorination, geminal
;
Radical deoxygenation, dehalogenation, nBu3SnH
;
Grob fragmentation, regiospecifity
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Azabicyclononanes by Fragmentation, II[1]. - Synthesis of 3-Azabicyclononanes by Regiospecific (Grob) FragmentationClemmensen reduction of the non-enolizable β1-dioxo group in the 1-azaadamantanedione derivative 1 gives the β1-hydroxy ketone 2, which is converted to the thioesters 3. Treatment of 3a or 3b with nBu3SnH/toluene yields the partially deoxygenated monoketone 4. Chlorination of 2 with SOCl2 generates 6 (geminal dichlorination). Dehalogenation with nBu3SnH produces 5. On the other hand, 2 can be monochlorinated to give 7, selectively. Preparative Grob fragmentation of the aza-tricyclic skeleton in 7 regiospecifically provides the 3-azabicyclo[3.3.1]nonane derivative 8. An even better access to 8 from 2 proceeds via an intermediate tosylate.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19931260512
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