PREPARATIONS 233 ethereal solution in turn with dilute sodium hydroxide solution (to ensure complete removal of the bisulphite) and lastly with a small quantity of water. Finally, in either case, dry the ethereal solution by shaking with powdered anhydrous potassium carbon-ate, and then distil off the ether from the filtered solution, using the usual apparatus for this purpose (p. 163): then replace the water-condenser by an air-condenser and distil the benzyl alcohol over a gauze, collecting the fraction of b.p. 200-207°. Benzyl alcohol is a colourless liquid of b.p. 205° and d , 1-04: it is almost odourless, and is only slightly soluble in water. Yield, 14 g. To obtain the benzoic acid, add an excess of concentrated hydrochloric acid carefully with stirring to the aqueous alkaline solution remaining from the original extraction. When no further precipitation of benzoic acid occurs, cool the solution (if percep-tibly warm) in ice-water, and then filter at the pump. Wash the benzoic acid thoroughly with cold water, drain, and then recrystal-
This is the end of the preview. Sign up
access the rest of the document.
This note was uploaded on 09/19/2011 for the course CHM 2211 taught by Professor Castalleano during the Fall '06 term at University of Florida.