OXIDATION-PRODUCTS OF TOTARA-8,11,13-TRIEN-13-OL DERIVATIVES

Reaction of 7-oxototara-8,11,13-trien-13-yl acetate (3) with acetic an hydride-perchloric acid affords the gamma-pyrone (8) in addition to th e previously reported acetyl derivative (4). Baeyer-Villiger oxidation s of the ketones (3) or (5) have given starting material or complex mi xtures, but the epsilon-lactone (9) and the rearranged product (11) we re isolated from two experiments with (3). Oxidation of 13-methoxytota ra-8,11,13-triene (2) with Jones reagent gives the 7-oxo derivative (5 ) and a low yield of a ring B opened substituted p-benzoquinone (13). Pathways to (11) and (13) are proposed.