A hypervalent iodine-mediated spirocyclization of 2-(4-hydroxybenzamido)acrylates - unexpected formation of δ-spirolactonesElectronic supplementary information (ESI) available: Experimental details, spectroscopic data, and copies of 1H and 13C NMR spectra for all new compounds. CCDC 900340 and 900341. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c2ob26815a

On the way towards a new total synthesis of ( S )-arogenate, a novel aryl-λ 3 -iodane-mediated oxidative spirocyclization of para -substituted phenol derivatives has been discovered. Starting from easy accessible 2-(4-hydroxybenzamido)acrylates we could construct spirocyclic lactams in up to 52% yield. Under alternative reaction conditions the same precursors underwent an unexpected oxidative spirocyclization yielding a novel δ-spirolactone in up to 70% yield. A novel iodane-mediated oxidative spirocyclization is reported that yields, depending on the reaction conditions, novel γ-spirolactams or unusual δ-spirolactones.