Org. Synth. 1937, 17, 84
Submitted by Donald Starr and R. M. Hixon.
Checked by John R. Johnson and H. B. Stevenson.
A 500-cc. three-necked flask
containing 114 g. (1.58 moles) of tetrahydrofuran (p. 566)
is fitted with a reflux condenser
, a thermometer
dipping into the liquid, and a bent glass tube
arranged to introduce gaseous hydrogen chloride (Note 1)
near the bottom of the flask. The upper end of the reflux condenser is connected to a 150-cc. distilling flask
cooled in an ice-salt mixture to trap material entrained by the hydrogen chloride
The tetrahydrofuran is heated to the boiling point (64–65°), and a slow stream of hydrogen chloride is bubbled into the liquid. As the reaction proceeds the temperature of the boiling liquid increases, slowly at first and then more rapidly, until it is above 100° (after about four hours' heating). At the end of about five hours the temperature remains practically constant in the range 103.5–105.5°, and the reaction is stopped. The light brown liquid is cooled, transferred to a 250-cc. Claisen flask having a 20-cm. fractionating side arm, and fractionated at reduced pressure, using a water aspirator. A large quantity of hydrogen chloride is evolved at the start of the distillation and a low pressure cannot be obtained until this has been removed. Throughout the fractionation a trap cooled to −15° in an ice-salt mixture is used to collect the recovered tetrahydrofuran.
After removal of a small amount of low-boiling material the main fraction distils in the range 80–90°/14 mm. or 65–75°/7 mm. (Note 2) and weighs 95–100 g. A small amount (5–10 g.) of high-boiling material remains. The crude product on refractionation yields 93–98 g. (54–57 per cent of the theoretical amount) of pure tetramethylene chlorohydrin boiling over a one-degree interval, 81–82°/14 mm. or 70–71°/7 mm. (Note 3) and (Note 4).
prepared by dropping concentrated sulfuric acid
into a mixture of sodium chloride and concentrated hydrochloric acid
may be used directly without drying.
It has been reported1
that tetramethylene chlorohydrin
undergoes loss of hydrogen chloride
when distilled at pressures appreciably above 15 mm. If an oil pump
is used for the distillation of the main fraction, it should be protected from hydrogen chloride
by means of soda-lime towers
For recovery of tetrahydrofuran
, the condensate from the cooling traps and the low-boiling material from the fractionations are combined, cooled in an ice bath
, and treated carefully with 15–20 cc. of 40 per cent alkali
. The upper layer is separated, dried with a little calcium chloride
, and distilled. The recovered tetrahydrofuran
, b.p. 64–67°
, weighs 20–22 g.
per cent of the original material). The residue (12–14 g.) remaining after distillation of the tetrahydrofuran
distils at 43–45°/10 mm.
and is tetramethylene dichloride
may be converted to the chlorobromide in excellent yields by the action of phosphorus tribromide
has been prepared by the action of thionyl chloride
on tetramethylene glycol
in the presence of pyridine
and by the method described above.2
Chemical Abstracts Nomenclature (Collective Index Number);
calcium chloride (10043-52-4)
sulfuric acid (7664-93-9)
hydrochloric acid (7647-01-0)
thionyl chloride (7719-09-7)
sodium chloride (7647-14-5)
phosphorus tribromide (7789-60-8)
1-Butanol, 4-chloro- (928-51-8)
tetramethylene dichloride (110-56-5)
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