Toluene → Spiro[imidazolidine-4,1′(2′H)-naphthalene]-2,5-dione

Participants

Reaction Steps

To a refluxing solution of 100 ml. of toluene containing 4.5 g. (0.019 mole) of 3',4'-dihydro-4'-hydroxyspiro [imidazolidine-4,1'(2'H)-naphthalene]2,-5-dione was added a trace of -toluenesulfonic acid and the refluxing continued for 2 hours. The reaction was cooled, stripped to dryness and the residue dissolved in 100 ml. of ethyl acetate. The organic phase was washed with a saturated sodium bicarbonate solution, dried over sodium sulfate and concentrated to dryness. The residue was triturated with diethyl ether, 2.7 g. (65% yield).

Provenance & Evidence