Geraldine Patricia Taber, D. Pfisterer, J. Colberg
Apr 24, 2004
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0
Influential Citations
66
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Journal
Organic Process Research & Development
Abstract
N-[4-(3,4-Dichlorophenyl)-3,4-dihydro-1(2H)-naphthalenylidene]methanamine, sertraline imine (3), is an intermediate for the synthesis of Zoloft, sertraline hydrochloride (1). A cleaner, simpler, and more efficient alternative to the Schiff base-mediated formation of sertraline imine has been developed and is presented in this paper. The condensation reaction between 4-(3,4-dichlorophenyl)-3,4-dihydro-1(2H)-naphthalone, sertraline tetralone (2), and monomethylamine was carried out in ethanol, without the need for classical dehydrating agent, such as TiCl4, or more novel approaches, such as molecular sieves, both of which produce hazardous byproducts and solid wastes. The low solubility of the imine 3 in this type of solvent is exploited, such that the reaction equilibrium favorably enhances the imine formation. Furthermore, an improved and highly selective catalytic reduction of 3 with Pd/CaCO3 catalyst in ethanol as the reaction solvent, followed by the resolution of the racemic cis isomer (6) with d-(−)-...