合成路线图解说明: (4-Chlorophenyl)acetonitrile (I) is reduced with DIBAL to the aldehyde (II), which is subsequently converted to enamine (III) by treatment with dimethylamine in the presence of CaCl2 as the dehydrating agent. Condensation of enamine (III) with 2-cyclohexenone (IV) produces a mixture of the trans endo/exo substituted bicycloalkanones (V) and (VI), separable by column chromatography. Reduction of the endo isomer (V) with NaBH4 yields the bicyclic amino alcohol as a diastereomeric mixture. After chromatographic isolation, the desired isomer is esterified with benzoyl chloride to furnish the corresponding amino ester, which is finally converted to the title hydrochloride salt. |