In a 2-l. round-bottomed flask fitted with a mechanical stirrer is placed a solution of 70 g. (1.75 moles) of sodium hydroxide in 400 cc. of water. To this solution is then added 230 g. (1.71 moles) of 2-chlorocyclohexanol (p. 158). The mixture is stirred vigorously for about one hour (Note 1). The stirring is then stopped and the upper layer is separated and fractionated carefully through an efficient column.

The fractions collected are 100–129°, 129–134°, and 134–175° (Note 2). The first fraction is mainly cyclohexene oxide but contains some water which is separated with a separatory funnel before the second fractionation. After the fraction boiling at 100–129° is collected, the condenser should be removed and dried thoroughly before collecting the second fraction, in order to insure anhydrous material. After two or three fractionations, the yield of cyclohexene oxide boiling at 129–134° is 117–122 g. (70–73 per cent of the theoretical amount).