Chemistry of hydrofluorenones. II. Synthesis from cyclohexyl benzoates

Abstract

Synthetically useful substituted hexahydrofluoren-9-ones and hexahydrobenzofluoren-11-ones may be prepared in one step from cyclohexyl benzoates or naphthoates and polyphosphoric acid. When the hydrindanone ring junctions are unsubstituted the stereochemistry may be determined from the ¹H N.M.R. spectra by decoupling the spectra after addition of a paramagnetic shift reagent.