Organic Chemical Manipulation - Softcover

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1897 edition. Excerpt: ...potash. Another distillation furnishes the isopropyl alcohol as a colourless liquid of boiling-point 88-84, miscible With water in all proportions. During this preparation a certain amount of the acetone.gets reduced in a different manner, tetramethylethylene glycol (a pinacone) being produced: 6. Preparation of Isopropyl Iodide (CH3-CHI'CH3).--Isopropyl iodide may be obtained from the alcohol by means of phosphorus and iodine; it is, however, more conveniently produced from glycerine. In a retort of suitable-size, provided with a condenser as shown in fig. 50, place 30 grams of iodine and 20 grams of glycerine (of sp. gr. 1'25), which has been diluted with 16 grams of water. Now add gradually in small portions at a time 5'5 grams of yellow phosphorus. (The addition of phosphorus must be made with care since there is already iodine in the retort.) The retort is then carefully heated, the contents being distilled as long as an oily liquid comes over. Eeturn the distillate to the retort and distil it over again. The liquid so obtained has next to be washed with dilute sodium carbonate solution and then with water in a separating funnel; finally it is separated from the water. dried over calcium chloride and rectified from a distilling flask. Colourless liquid, boiling-point 89'5. Specific gravity 1'7109 at 15 (Linnemann). In this preparation the iodine and phosphorus form phosphorus iodide which reacts on the glycerine, forming, not propenyl triodide C3H5I3, but allyl iodide, C3H5I: C3H6(OH)2 + PI3 = H3P03 + I, + C3H5I. The iodine is not obtained in the free state, but as hydrogen iodide under the influence of the water and phosphorus present. This, then, serves to reduce the allyl iodide to isopropyl iodide: CH, CH3 I I' CH + 2 HI = CHI +...