A dry
12-l. three-necked flask is equipped with an efficient motor-driven stirrer (Note
1),
a nitrogen inlet tube, a large Allihn condenser, and a 1-l. separatory funnel. Both the condenser and the funnel are provided with
calcium chloride drying tubes. To the flask is added
146 g. (6 gram atoms) of magnesium turnings (Note
2), and
nitrogen gas, first bubbled through concentrated
sulfuric acid, is passed in to displace the air. During the reaction the
nitrogen atmosphere is maintained. The
magnesium is covered with
200 ml. of anhydrous ether, and a few milliliters of a solution of
852 g. (6 moles) of methyl iodide in
1 l. of anhydrous ether is added from the separatory funnel. The reaction starts spontaneously, and then the remainder of the
methyl iodide solution is added slowly. When the reaction is complete (Note
3),
4 l. of dry benzene is added, a condenser is arranged for downward distillation, and about 1.2 l. of solvent is distilled (Note
4). The condenser is changed to a reflux position,
609 g. (3 moles) of 9-cyanophenanthrene (p. 212) is added quickly through a powder funnel, and the mixture is heated and stirred under reflux for 3 hours. It is then cooled in an
ice bath to 0°,
3 l. of cold 6 N hydrochloric acid is slowly added (
Caution!) from a separatory funnel with stirring, and the mixture is refluxed for 6 to 8 hours (Note
5).
After cooling, the layers are separated, the organic layer is washed with dilute
sodium bicarbonate solution and placed in a flask equipped for distillation, and the solvent is distilled The oily residue is transferred while still warm to a
1-l. Claisen flask, and the product is distilled under reduced pressure; b.p.
190–200°/2.5 mm. (
168–170°/1 mm.). The yield is
400–430 g. (
61–65%). The distilled ketone is recrystallized once from
ethanol (1.5–2 l.) to yield
345–390 g. (
52–59%) of
9-acetylphenanthrene of m.p.
73–74°.