Org. Synth. 1944, 24, 81
DOI: 10.15227/orgsyn.024.0081
p-NITROBENZYL ALCOHOL
[Benzyl alcohol, p-nitro]
Submitted by W. W. Hartman and E. J. Rahrs.
Checked by R. L. Shriner and Charles Russell.
1. Procedure
A solution of
218 g. (1.12 moles) of p-nitrobenzyl acetate (p. 650) in
500 ml. of hot methanol is prepared in a
2-l. flask. To the hot solution is added
380 g. (1.43 moles) of a 15% solution of sodium hydroxide. The alkali should be added slowly at first with shaking to prevent too vigorous boiling. After standing for 5 minutes, the mixture is poured with vigorous hand stirring into 4.5 kg. of a mixture of cracked ice and water. The precipitate is collected on a
Büchner funnel and recrystallized from 3 to 3.7 l. of hot water with the aid of
15 g. of Norit. The alcohol is dried at 60° to 65° in an
oven for several hours and bottled
(Note 1). The yield of slender, nearly colorless needles amounts to
110–121 g. (
64–71%); the product melts at
92–93° (Note 2).
2. Notes
1.
The product turns yellow if it is spread out to dry in the air.
2.
The submitters report that
p-iodobenzyl alcohol can be prepared in a similar manner, and that it is unnecessary to isolate the acetate. A mixture of
148 g. of p-iodobenzyl bromide,
52 g. of potassium acetate, and
750 ml. of 95% ethanol is refluxed for 8 hours, cooled, and filtered from the salt. To the filtrate is added
33.6 g. of potassium hydroxide, and the solution is refluxed for 6 hours. It is then diluted with 2 l. of water, and the oil taken up in
500 ml. of chloroform. After concentration to 150 ml. and chilling,
p-iodobenzyl alcohol crystallizes. It is filtered and the solid rinsed with
petroleum ether; the rinse added to the mother liquor causes the separation of an additional amount of
p-iodobenzyl alcohol. The combined yield is
95–100 g. (
81–86%); the product melts at
70–72°.
3. Discussion
p-Nitrobenzyl alcohol has been secured by the oxidation of
p-nitrotoluene electrolytically
1 or chemically,
2 by the reduction of
p-nitrobenzaldehyde with
formaldehyde in alkaline solution,
3 and by the hydrolysis of the acetate.
4,5 p-Iodobenzyl alcohol has been prepared by hydrolysis of
p-iodobenzyl bromide and
p-iodobenzyl acetate.
6,7
Appendix
Chemical Abstracts Nomenclature (Collective Index Number);
(Registry Number)
petroleum ether
ethanol (64-17-5)
methanol (67-56-1)
sodium hydroxide (1310-73-2)
formaldehyde (50-00-0)
chloroform (67-66-3)
Norit (7782-42-5)
potassium hydroxide (1310-58-3)
potassium acetate (127-08-2)
p-Nitrobenzaldehyde (555-16-8)
p-iodobenzyl acetate
p-Nitrobenzyl alcohol,
Benzyl alcohol, p-nitro (619-73-8)
p-nitrotoluene (99-99-0)
p-Nitrobenzyl acetate (619-90-9)
p-iodobenzyl alcohol (18282-51-4)
p-iodobenzyl bromide (16004-15-2)
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