PREPARATIONS 289 [NOTE. Hydrocarbons such as ethyl-benzene can also be prepared by the Clemmensen reduction of the corresponding ketone. This is exemplified by the reduction of />-methylacetophenone (p. 290)]. Required: Sodium, 22-5 g.; dry ether, ioo ml.; bromoben-zene, 34 ml.; ethyl bromide, 31 ml. Using the sodium press described on p. 82, press 22-5 g. of sodium into wire, and allow the latter to fall directly into ioo ml. of anhydrous ether (preparation, p. 82) contained in a 750 ml. round-bottomed flask. Fit the latter with an efficient (preferably double-surface) reflux water-condenser, and stand the flask on a cork ring. Now pour down the condenser a mixture of 34 ml. (50 g.) of dry bromobenzene and 31 ml. (45-5 g., i.e., a 30% excess) of ethyl bromide. Close the top of the condenser with a calcium chloride tube and shake the mixture thoroughly. After 10-15 minutes, the reaction will cause the ether to boil steadily. Shake the mixture occasionally during the next two hours in order to prevent the wire from becoming coated
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