ZerZ-Alcohols

Contact of the acid with sec- or ZerZ-alcohols, even with cooling, may lead to violent explosions [1]. The autodetonation region which exists for the hydrogen perozdde-suUuric acid —2-propanol or-ZcrZ-butanol system is shown on a triangular diagram [2]. 

In a 250 ml. separatory funnel place 25 g. of anhydrous ZerZ.-butyl alcohol (b.p. 82-83°, m.p. 25°) (1) and 85 ml. of concentrated hydrochloric acid (2) and shake the mixture from time to time during 20 minutes. After each shaking, loosen the stopper to relieve any internal pressure. Allow the mixture to stand for a few minutes until the layers have separated sharply draw off and discard the lower acid layer. Wash the halide with 20 ml. of 5 per cent, sodium bicarbonate solution and then with 20 ml. of water. Dry the preparation with 5 g. of anhydrous calcium chloride or anhydrous calcium, sulphate. Decant the dried liquid through a funnel supporting a fluted Alter paper or a small plug of cotton wool into a 100 ml. distilling flask, add 2-3 chips of porous porcelain, and distil. Collect the fraction boiling at 49-51°. The yield of ferf.-butyl chloride is 28 g. 

Jeanes and associates23 used the ratio of the RF values of maltose and D-glucose as a criterion for choosing suitable solvent mixtures. The adaptability of ternary solvent mixtures was commended. After testing a number of mixtures made up of an alcohol (1-butanol, ethanol, or fusel oil), an acid or base, and water, as well as collidine-pyridine-water mixtures, they recommended basic mixtures, in particular, 1-butanol-pyridine-water. The composition of mixtures containing acid may change as a result of esterification. For example 1-butanol-acetic acid-water mixtures should be allowed to stand for some time before use.21 To obviate esterification of solvent, Hanes and Isherwood used ZerZ-pentyl alcohol in solvent mixtures containing acid.30... 

Fair 7i-propyl alcohol (40%), isobutyl alcohol, scc.-butyl alcohol, 2-methyl-1-butanol, isoamyl alcohol, ZerZ.-amyl alcohol, menthol Poor ethyl alcohol (30%), benzyl alcohol... 

Figure 8.7. Composition profiles for Example 8.3.1. Arrows indicate directions of mass transfer. ZerZ-Butyl alcohol is transported towards the interface when its own driving force suggests transfer away from the interface.

ZerZ-Butyl alcohol is the common name for 2-methyl-2-propanol. 

The benzene and unchanged ZerZ.-butyl alcohol are removed by distillation from the steam bath, the final traces being removed under 10-30 mm. pressure. A liter of dry ether is added, and the solid aluminum tert. -butoxide is dissolved by refluxing for a short... 

Ether and ZerZ.-butyl alcohol are removed by distillation at atmospheric pressure without a column, and the xylene is removed by distillation through a 35-cm. Vigreux column at 25-50 mm. The residue is transferred to a smaller flask, and the acetophenone is first distilled at about 80°/10 mm., and finally the dypnone is distilled at 150-155°/ mm. (Notes 7 and 8). The yield is 85-91 g. (77-82 per cent of the theoretical amount) of a yellow liquid. 

Commercial ZerZ,-butyl alcohol dried over calcium oxide is suitable for this preparation. Aluminum isopropoxide or ethoxide may be used in place of the aluminum ZerZ.-butoxide to remove traces of water. The grade of metal known as fast cutting rods has proved most satisfactory. The checkers used turnings made from aluminum cast from melted-down kitchen utensils. Aluminum Zer/.-butoxide has also been prepared successfully in another laboratory from commercially pure aluminum (2S) and from rods of the alloy 17ST (communication from L. F. Fieser). The checkers were able to obtain considerably higher yields of the butoxide from pure aluminum than from a copper-bearing alloy. 

In a I-l. round-bottomed, three-necked flask, fitted with a thermometer, an efficient mechanical stirrer (Note i), and a 35-cm. Vigreux column fitted to a condenser and receiver protected by a calcium chloride tube, are placed 345 g. (400 cc.) of dry xylene, 120 g. (117 cc., i mole) of dry acetophenone, and 135 g. (0.55 mole) of aluminum ZerZ.-butoxide (p. 8) (Note 2). The stirrer is started and the flask heated in an oil bath so that the temperature of the reaction mixture is held between 133° and 137°. ZerZ.-Butyl alcohol slowly distils at a temperature in the vapor of 80-85°. The distillation of the alcohol can be accomplished by maintaining the temperature of the heating bath between 150° and 155° for two hours after distillation has commenced (Notes 3 and 4). 

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