Iodocarbocyclization of α-iodocycloalkanones bearing an allenyl side chain: synthesis of spirocyclic cycloalkanones

AlCl3/ICl-mediated iodocarbocyclizations of α-iodocycloalkanones bearing an allenyl side chain are described. Treatment of iodocycloalkanones 4a-i with AlCl3/ICl gave spirocyclic cycloalkanones 5a-i and 6a-i as a mixture of products.