A synthetic approach to cyclo-octa-2,5,7-triene-1,4-dione

Abstract

Cyclo-octa-2,5,7-triene-1,4-dione bisethylene aceta1 [(13) or (14)] has been prepared by bromination of cyclooctane-1,4-dione bisethylene acetal (11) to give the tribromo-compound (12), and subsequent dehydrobromination. The dibromo-trans-cyclo-octene bisacetal (17) is an intermediate in the dehydrobromination reaction, but it was not possible to distinguish spectroscopically between structures (13) and (14) for the triene bisacetal. The triene bisacetal could not be converted into cyclo-octa-2,5,7-triene-1,4-dione (3).