Organic Syntheses, CV 2, 317
Submitted by Frank C. Whitmore and T. Otterbacher.
Checked by Henry Gilman and H. J. Harwood.
1. Procedure
In a
3-l. round-bottomed flask, fitted with an
efficient Liebig condenser (100 by 1 cm.),
228 g. (2 moles) of methyl n-amyl ketone (Org. Syn. Coll. Vol. I, 1941, 351) is dissolved in a mixture of
600 cc. of 95 per cent alcohol and 200 cc. of water.
One hundred thirty grams (5.6 gram atoms) of sodium in the form of wire is gradually added through the condenser. During the addition of the
sodium the flask is cooled with running water (Note
1) so that the reaction does not become unduly violent (Note
2).
When the
sodium has dissolved (Note
3), 2 l. of water is added and the mixture is cooled to 15°. The upper oily layer is then separated, washed with
50 cc. of 1:1 hydrochloric acid and then with 50 cc. of water, dried over
20 g. of anhydrous sodium sulfate, and distilled with a
fractionating column (Note
4). After a small fore-run of low-boiling liquid, the pure
heptanol distils at
155–157.5°. The yield is
145–150 g. (
62–65 per cent of the theoretical amount).
2. Notes
1. If no cooling is used, condensation products are formed and the yield of
heptanol is reduced considerably.
2. The temperature can be held conveniently below 30° by cooling with ice. Such cooling when accompanied by stirring is particularly helpful during the early addition of the
sodium (either as wire or in small pieces). With cooling and stirring, very little refluxing takes place and after the addition of about
60 g. of sodium the reaction slows down to such an extent that large amounts of
sodium can be added at once without danger of excessive heating.
3. The time required for addition of the
sodium may be significantly decreased by the use of mechanical stirring. Although the yield is not increased appreciably by stirring, frothing is prevented and for this reason the
sodium may be added more rapidly.
4. The submitters used a
Young column with 20 disks 3 cm. apart. The checkers used a
Glinsky three-bulbed column.
3. Discussion
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