In a
2-l. three-necked flask, fitted with a
mercury-sealed stirrer,
thermometer,
condenser, and
dropping funnel, is placed
684 g. (845 cc., 9.2 moles) of dry n-butyl alcohol (Note
1). The condenser is connected to a
trap for absorbing
hydrogen chloride, and
500 g. (305 cc., 4.2 moles) of thionyl chloride (Note
2) is added over a period of two hours, with stirring. The reaction mixture is kept at 35–45°, by immersing the flask in ice water, during the addition of the first half of the
thionyl chloride (Note
3). After evolution of
hydrogen chloride begins, the
water bath is removed and a small flame applied to maintain this temperature. After all the
thionyl chloride has been added the temperature is raised gradually to the boiling point, over a period of thirty minutes, to complete the reaction and remove the remainder of the
hydrogen chloride. The reaction mixture is then transferred to a
1-l. modified Claisen flask with a 25-cm. fractionating side arm, and fractionated under diminished pressure. After a fore-run consisting largely of unchanged alcohol, there is obtained
625–689 g. (
77–84 per cent of the calculated amount) of
n-butyl sulfite, b.p.
109–115°/15 mm. Refractionation gives
585–674 g. (
72–83 per cent) of a product distilling at
109–112° at 14 mm. (Note
4).