Resumen

COSTA, Jessé S. da et al. Lewis acid promoted Friedländer condensation reactions between anthranilonitrile and ketones for the synthesis of tacrine and its analogues. J. Braz. Chem. Soc. [online]. 2009, vol.20, n.8, pp. 1448-1454. ISSN 0103-5053.  http://dx.doi.org/10.1590/S0103-50532009000800009.

The scope of Lewis acid-promoted cyclodehydratation reactions between anthranilonitrile and several ketones, to afford tacrine and its derivatives, was expanded to include the use of various metal chloride salts not reported in the literature. The ability of the Lewis acids to effectively promote the cyclodehydratation between anthranilonitrile and cyclohexanone as the ketone was found to be the following order: InCl₃ > AlCl₃ ~ BF₃.Et₂O > FeCl₃ > BiCl₃ ~ SbCl₃ ~ SnCl₂.2H₂O. The reactions were performed under both solvent and solvent-free conditions in good to excellent yields. Other Lewis acids screened, such as RuCl₃, CeCl₃, NiCl₂, CoCl₂.2H₂O and CsCl were not effective.

Palabras llave : tacrine analogues; Lewis acid; Friedländer reaction; Alzheimer's disease.