Ene-sulfonamides, obtained from epoxy (terminal as well as internal) benzenesulfonamide and substituted chloro-acrylaldehydes, undergo Lewis acid (BF3·OEt2) catalysed cyclisation to afford azabicyclononene, tetrahydropyridinyl benzoate or tetrahydropyridine-carbaldehyde scaffolds depending on the substrate. In the presence of Me3SiN3, substituted tetrazoles are readily obtained. Key products have been characterized by single-crystal X-ray crystallography.
