Journal of the Brazilian Chemical Society
versión On-line ISSN 1678-4790
MACHADO, Melina A.; HARRIS, Maria Inês N. C. y BRAGA, Antonio C. H.. Studies on the reduction of b-enamino ketones. J. Braz. Chem. Soc. [online]. 2006, vol.17, n.7, pp. 1440-1442. ISSN 1678-4790. http://dx.doi.org/10.1590/S0103-50532006000700036.
Reduction of b-enamino ketones 1 with NaBH(OAc)3 in glacial acetic acid gave b-amino ketones 3 in 65% to 67% yield. These data and others observed in the reduction of b-enamino ketones 1 to preferentially syn g-amino alcohols 2 with NaBH4/HOAc suggest that in this last reaction we have firstly the reduction of the b-enamino ketones 1 to produce the b-amino ketones 3, and then this compound is reduced to the g-amino alcohols 2. We can say from this results that the diastereosselectivity of the reduction of b-enamino ketones 1 to mainly syn g-amino álcohols 2, can be analysed as a competition between a chair-like transition state and a boat-like transition state, obtained from the b-amino ketones 3.
Palabras clave : amino alcohols; enamino ketones; amino ketones; Mannich base.