Abstract
One of oxidation products from (±)-cis-chrysanthemic acid with aqueous potassium permanganate was an acid melting at 243°C, which had been believed to be an isomer of (±)-cis-dihydroxydihydrochrysanthemic acids, but the structure of the acid was confirmed to be an acetal of (±)-cis-caronhalfaldehydic acid with (±)-cis-dihydroxydihydrochrysanthemic acid. On the other hand, an acid melting at 189°C was isolated from the same oxidation mixture, which afforded a lactol of (±)-cis-caronhalfaldehydic acid by the oxidation with aqueous periodic acid, and afforded (±)-cis-ketol-chrysanthemic acid by the oxidation with aqueous potassium permanganate.
(±)-cis-Ketol-chrysanthemic acid was converted to already known (±)-trans-ketol-chrysanthemic acid on heating with aqueous sodium hydroxide. Now the acid melting at 189°C was confirmed to be an isomer of (±)-cis-dihydroxydihydrochrysanthemic acid.
