ISSN:
0170-2041
Keywords:
2-Azabicyclo[3.3.1]nonanes
;
Morphanes
;
Cyclohexanone, 4-acetamido
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Stereoselective Synthesis of the Substituted Morphane Framework Starting with 4-Acetamidocyclohexanone4-Acetamidocyclohexanone (2), prepared from 4-acetamido-cyclohexanol (1), has been transformed into the ethyleneacetal 3b which was amidated with pyruvic and 2-oxobutyric acid to give 3c and d, respectively. After removal of the protecting group (4a, b) the amide is treated with sodium hydride in tetrahydrofuran or with sodium ethylate in ethanol. Depending on the reaction conditions 4b is transformed into the aldol 6 or the cyclised aldol 5b (5a from 4a, respectively) with 2-azabicyclo[3.3.1]nonane structure and endo-positioned hydroxy group. Constitution and stereochemistry has been proved by X-ray structure analysis of 7a. The stereochemistry of the ring closure reaction corresponds to the transition state postulated.
Additional Material:
3 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.1990199001146
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