Tandem Michael addition - Hoffman elimination sequence of DMAD on tetrahydropyrrolo[3,2-C]pyridines. New route to vinylpyrroles.

The reaction of tetrahydropyrrolo [3,2-c]pyridlines with DMAD in THF at room temperature results in piperidine ring cleavage producing alpha- or beta-vinylpyrroles in moderate to good yields. The resulting compounds are hardly available by other synthetic means and are good candidates for further transformations.