A fine-tuning of photoreactivity of large ring 2-phenylcycloalkanones adsorbed in cyclodextrins

The photochemistry of solid complexes of large ring 2-phenylcycloalkanones adsorbed in cyclodextrin cavities results in significant yields of enals as disproportionation products, at the expense of the para-rearrangement, depending on both the ring size of the cyclanone and the cavity size of the cyclodextrin. This behavior contrasts with its photoreaction in homogeneous solutions which yields predominantly para-cyclophanes.