Hydrochloric Acid → 5'-Ethoxyspiro(cyclohexane-1,2'-indan)-1',4-dione 4-ethylene ketal

Participants

Reaction Steps

A mixture of 1.86 g. (0.0072 mole) of 3',4'-dihydrospiro[cyclohexane-1,2'(1'H)-naphthalen]-4-one, ethylene ketal (8) (prepared in Example 7C) and 2 ml. of 2.5 N hydrochloric acid in 40 ml. of acetone is heated at reflux for about 17 hours. Most of the solvent is removed under vacuum and the residue dissolved in water and ether. The organic layer is washed with water and brine and then evaporated to dryness to give 3',4'-dihydrospiro[cyclohexane-1,2'(1'H)-naphthalen]-4-one (9).

Provenance & Evidence