Reactions of 1,4-diaryl-2,3-dioxabicyclo[2.2.2]oct-5-enes 1a-c (la: Ar=p-FC6H4, 1b: Ar=C6H5 1c: Ar=p-MeC6H4) with FeBr2 afforded syn-1,2;3,4-bis(epoxy)-1,4-diarylcyclohcxanes 4a-c and cis-3,6-diaryl-2,3-epoxycyclohexanones 5a-c as major products instead of the previously reported 1-aroyl-3-aryl-2,3-epoxycyclopentanes 2a-c. (C) 2002 Elsevier Science Ltd. All rights reserved.