The known methoxyhexahydrofluorenone 6 has been converted into acids 1-4 desired as models for study of transformations in the aromatic ring. Of the various methods used to introduce the carboxyl functions, the selective lithium-hydrogen exchange and subsequent carbonation reactions applied to the olefins 10 and 35 and to alcohol 8 are worthy of special note. © 1969, American Chemical Society. All rights reserved.