PREPARATION OF TERTIARY B U T n CHLORIDE
Most teachers of elementary organic chemistry have certain favorite preparations which they require of their students in the laboratory work. Rut all of these teachers labor under one obvious handicap, that the majority of the preparations usually require considerable time. Of course this is due to the fact that most organic reactions are "time-reactions," and is no fault of the teachers. I t would seem then that any satisfactory preparation illustrating one or more important principles, and economical as regards time, might be of interest to teachers of organic chemistry. The author wishes to suggest for consideration a preparation which is required in his classes in organic chemistry. It is the preparation of t e r ~ tiary butyl chloride by the action of hydrochloric acid o n tertiary butyl alcohol. It illustrates two important principles: first, the synthesis of an alkyl halide from the corresponding alcohol, and second, the lability of the hydroxyl group in the tertiary alcohol as compared to that in the primary or secondary alcohols. The time required for the experiment varies from two minutes to several hours, depending upon the details required by the teacher. Briefly, if equal volumes of tertiary butyl alcohol and concentrated hydrochloric acid (sp. gr. 1.18) are shaken together, tertiary butyl chloride will separate as the top layer in the container in a short time, usually in two or three minutes. More detailed directions are as follows: Mix 50 ml. of tertiary butyl alcohol ("practical" quality is satisfactory) with 50 ml. of concentrated hydrochloric acid (sp. gr. 1.18) in a gyass-stoppered separatory funnel. Shake vigorously for several minutes, allow the layers t o separate distinctly, drain off, and discard the bottomlayer. To the top layer in the funnel add approximately 25 ml. of water and 1 g. of potassium carbonate. Shake, discard the aqueous layer, and empty the top layer into a flask containing about 5 g. of anhydrous potassium carbonate which is used for drying purposes. Agitate for several minutes, filter offthe and allow the filtrate. susoension of ootassium carbonate hv means of a dry filter DaDer . t m i a r y butyl chlnridr. to t l o ~ dtrcrtly into a tared hottlu. The usunl yicld is 30-40'; of the thcorctical. Of nlufir. sd.stitfrtion of hsdrohromic wid for the hsrlrochloric acid gives the tertiary butyl bromide. ~
Mention should be made here of the article by Davis and Murray1 which originally suggested the above class preparation to the author. ' Davis and Murray, I d Eng. Chem., 18,844 (1926).
Far above the conqueror of kingdoms, t h e destroyer of hosts by the sword or bayonet, is he whose peerless victories redden no river or whiten no plain, who rears his empires, not on the bleeding fragments of ~ubjugatednations, but upon the realms of intellect which he has discovered and planted, and peopled with beneficient and enduring joy.-HORACE GREELEY 313
