Conversion of a trans–syn–trans to a cis–syn–trans perhydrobenz[e]indenone triggered by intramolecular 1,5-hydrogen transfer

The conversion of a trans–syn–trans perhydroiodomethyltrimethylbenz[e]indenone to the corresponding cis–syn–trans perhydrobenz[e]indenone occurred during the reduction of the iodomethyl to a methyl group under radical conditions.