In a 5-l. round-bottomed flask, fitted with a stirrer, separatory funnel, and a reflux condenser to the upper end of which a calcium chloride tube is attached, is placed 150 g. (6.2 atoms) of magnesium turnings. A small crystal of iodine (Note 1) and about 100 cc. of a mixture of 822 g. (6 moles) of n-butyl bromide (p. 28) and 2 l. of anhydrous ethyl ether are added. As soon as the reaction starts, 350 cc. of anhydrous ether is added, and the remainder of the n-butyl bromide solution is dropped in at such a rate that the mixture boils continuously. The time of addition (one and one-half hours) may be decreased by cooling the flask externally. Stirring is started as soon as enough liquid is present in the flask.

When all has been added (Note 2), 278 g. (6.3 moles) of ethylene oxide (Note 3) (previously dried with soda lime) is added through a tube (3 or 4 mm. in diameter) the end of which is about 20 mm. above the surface of the liquid (Note 4), the temperature being kept below 10° by cooling in an efficient ice-and-salt bath (Note 5). This addition requires four to six hours. When all has been added the ice bath is removed; the temperature of the mixture generally rises enough to cause gentle boiling. When this ceases the mixture is warmed on a steam bath for one hour longer.

The condenser is then arranged for downward distillation, and when about 1 l. of ether has distilled (Note 6) the receiver is changed and 1 l. of dry benzene (Note 7) is added; distillation is continued with stirring until the temperature of the distilling vapor reaches 65°. The mixture is then boiled under reflux for one hour. Usually by this time it has become so viscous that stirring is no longer efficient. The mixture is then allowed to cool and is decomposed with 2 l. of an ice-water mixture. The precipitated magnesium hydroxide is dissolved by adding a sufficient quantity of 30 per cent sulfuric acid and enough ice to keep the mixture cold.

The mixture of benzene and hexyl alcohol is now distilled in a current of steam; about 7 l. of distillate must be collected before all the product is distilled. The oily layer is separated and the watery portion distilled until free of hexyl alcohol. The oil so obtained is added to the main quantity and the watery portion again distilled. The united product is now stirred on the steam bath for one to two hours with 1 l. of 20 per cent sodium hydroxide solution and again subjected to steam distillation, as before. The oily product so obtained is then distilled under atmospheric pressure with the use of a good fractionating column. The fraction boiling up to 85° is mostly benzene and water. The fraction boiling between 85° and 154° is collected separately for redistillation, and the fraction boiling at 154–157° collected as pure material. There is practically no high-boiling residue. The yield (Note 7) is 368–380 g. (60–62 per cent of the theoretical amount) (Note 8).