Addition of Nucleophiles to Immonium Galanthamines

Four galanthamine derivatives were converted into immonium bromides by treatment with NBS. The nucleophilic addition of cyanide and methylmagnesium iodide to these galanthaminium halides was studied and the structures and conformations of two products were investigated by NMR spectroscopy and X-ray diffraction. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)