ISO PRACTICAL ORGANIC CHEMISTRY calcium chloride). Then fractionally distil the dried liquid up a short column, and collect the fraction of b.p. 150-180° (mainly at 170-172°). Work up the product by method (a) or (b): method (b) affords the anhydrous pinacol. (a) Cool the fraction of b.p. 150-180° in ice-water, and add water (ca. 5 ml.) dropwise with stirring. The crystalline hexa-hydrate of pinacol is formed with considerable heat evolution: directly the product becomes solid, stop adding water, for an excess will redissolve the hexahydrate. Transfer the hexahydrate (yield 10-11 g.) on to a pad consisting of several thicknesses of drying-paper, and press it with another pad to remove all mois-ture, transferring the hydrate if necessary to a fresh pad to com-plete the drying. Then store it in a bottle having a well-fitting stopper. The sample may be recrystallised from water (ca. io ml.) before drying: yield of pure hexahydrate, 9 g. (b)
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.