AN APPROACH TO THE SYNTHESIS OF STIPITATIC ACID
MAUPIN, PAUL HUTSELL, II
Doctor of Philosophy
An approach to the synthesis of the penicilium mold metabolite stipitatic acid has been investigated. It involved the preparation of a bis-(alpha)-diazoketone derived from citric acid, whose central (alpha)-hydroxy acid function had been masked and protected, and its conversion into a 6,6-disubstituted 2-cycloheptene-1,4-dione by intramolecular diazoketone coupling catalyzed by bis-cyclopentadienylnickel (nickelocene). Bromination of the enedione, followed by dehydrobromination, yielded a bromoenedione. (beta)-Elimination of both enediones with potassium hydroxide gave (gamma)-tropolones. Alakali treatment of the bromotropolone afforded a phenolic ring contraction product.