A general approach to E,E-diene hydroperoxides is described based upon
photoisomerization oi readily available Z,E-diene monoperoxyketals. P
rotection of a Z,E-diene hydroperoxide as the 2-methoxypropyl peroxyke
tal is followed by iodine-mediated photoisomerization to produce a mix
ture enriched in the E,E isomer. After chromatographic purification, d
eprotection of the peroxyketal with mild acid furnishes the E,E-diene
hydroperoxide.