A Publication
of Reliable Methods
for the Preparation
of Organic Compounds
Annual Volume
Org. Synth. 1940, 20, 50
DOI: 10.15227/orgsyn.020.0050
Submitted by C. S. Marvel and V. C. Sekera.
Checked by C. F. H. Allen and C. V. Wilson.
1. Procedure
In a 1-l. three-necked flask fitted with a stirrer and thermometer are placed 93 g. (0.5 mole) of dodecanol (Note 1) and 158 g. (2 moles) of pyridine. The flask is surrounded by a water bath sufficiently cold to lower the temperature of the mixture to 10°. At this temperature 105 g. (0.55 mole) of p-toluenesulfonyl chloride is added in portions over a 20- to 30-minute period, or at such a rate that the temperature does not exceed 20° at any time. The mixture is then stirred for 3 hours at a temperature below 20°, after which it is diluted with 300 ml. of hydrochloric acid (sp. gr. 1.19) in 1 l. of ice water. The ester which crystallizes is collected on a chilled Büchner funnel and sucked as dry as possible. The solid is transferred to a 600-ml. beaker, 250–300 ml. of methanol is added, and the mixture is warmed on the steam bath until the ester melts. It is then cooled in a freezing mixture while being stirred continuously; the ester separates in a fairly fine state. It is then collected on a chilled funnel and allowed to dry in the air, preferably at a temperature below 20°. The yield of ester is 152–156 g. (88–90% based upon the dodecanol used). It melts at 20–25° (Note 2) and is sufficiently pure for most purposes.
If a purer product is desired, it is recrystallized from petroleum ether (b.p. 30–60°), using 4 ml. per 3 g., and drying over anhydrous sodium sulfate. The solution is chilled to 0° and the ester filtered on a chilled funnel; the recovery is 90%, and the melting point is 28–30°. Evaporation of the solvent to a small volume deposits an additional amount (Note 3).
2. Notes
1. Dodecanol (lauryl alcohol), m.p. 20–22°; pyridine, b.p. 113–115°; and p-toluenesulfonyl chloride, m.p. 66–68°, are used.
2. The ester contains traces of water, which makes the melting point unreliable; the freezing point is 24–25°.
3. The following esters have been made in essentially the same yields; butyl p-toluenesulfonate [Org. Syntheses Coll. Vol. 1, 145 (1941)]; n-tetradecyl p-toluenesulfonate, m.p. 35°; n-hexadecyl p-toluenesulfonate, m.p. 49°; n-octadecyl p-toluenesulfonate, m.p. 56°; n-decyl p-bromobenzenesulfonate, m.p. 43–44°; n-dodecyl p-bromobenzenesulfonate, m.p. 49°; n-tetradecyl p-bromobenzenesulfonate, m.p. 51.5°; n-hexadecyl p-bromobenzenesulfonate, m.p. 60°; n-octadecyl p-bromobenzenesulfonate, m.p. 64–65°.
3. Discussion
n-Dodecyl p-toluenesulfonate has been prepared only by the action of p-toluenesulfonyl chloride on dodecanol-1 in the presence of pyridine1 according to the general procedure developed by Patterson and Frew2 for making esters of sulfonic acids.
This preparation is referenced from:

References and Notes
  1. Sekera and Marvel, J. Am. Chem. Soc., 55, 345 (1933).
  2. Patterson and Frew, J. Chem. Soc., 89, 332 (1906).

Chemical Abstracts Nomenclature (Collective Index Number);
(Registry Number)

petroleum ether

hydrochloric acid (7647-01-0)

methanol (67-56-1)

Lauryl alcohol,
dodecanol-1 (112-53-8)

sodium sulfate (7757-82-6)

pyridine (110-86-1)

p-Toluenesulfonyl chloride (98-59-9)

n-Dodecyl p-toluenesulfonate (10157-76-3)

Butyl p-toluenesulfonate (778-28-9)


n-tetradecyl p-toluenesulfonate

n-hexadecyl p-toluenesulfonate

n-octadecyl p-toluenesulfonate (3386-32-1)

n-decyl p-bromobenzenesulfonate

n-dodecyl p-bromobenzenesulfonate

n-tetradecyl p-bromobenzenesulfonate

n-hexadecyl p-bromobenzenesulfonate

n-octadecyl p-bromobenzenesulfonate