Allenyl vinyl ketones were exposed to titanium and indium halides in order to carry out Nazarov cyclizations. Whereas TiI 4 and InX 3 (X=Cl, Br, and I) led to cyclopentenones in which a halogen was trapped highly regioselectively, the reactions mediated by TiBr 4 gave mixtures of brominated isomers. When the allenyl vinyl ketones were treated first with Br 2 and then with TiBr 4 , doubly brominated cyclopentenones resulted, and treatment with I 2 followed by TFA gave cyclopentenones bearing both hydroxyl and iodo groups.