High boiling point materials

Reflux a mixture of 68 g. of anhydrous zinc chloride (e.g., sticks), 40 ml. (47 -5 g.) of concentrated hydrochloric acid and 18-5 g. (23 ml.) of sec.-butyl alcohol (b.p. 99-100°) in the apparatus of Fig. 777, 25, 1 for 2 hours. Distil oflF the crude chloride untU the temperature rises to 100°. Separate the upper layer of the distillate, wash it successively with water, 5 per cent, sodium hydroxide solution and water dry with anhydrous calcium chloride. Distil through a short column or from a Claisen flask with fractionating side arm, and collect the fraction of b.p. 67-70° some high boiling point material remains in the flask. Redistil and collect the pure cc. butyl chloride at 67-69°. The yield is 15 g. 

The solution may be rendered homogeneous by the addition of ethyl alcohol, but the yield appears to be slightly diminished and more high boiling point material is produced. 

Pour the reaction mixture cautiously into 400 g. of crushed ice and acidify it in the cold by the addition of a solution prepared by adding 55 ml. of concentrated sulphuric acid to 150 ml. of water and then coohng to 0°. Separate the ether layer and extract the aqueous layer twice with 50 ml. portions of ether. Dry the combined ethereal solutions over 50 g. of anhydrous potassium carbonate and distil the filtered solution thror h a Widmer column (Figs. II, 17, 1 and II, 24, 4). Collect separately the fraction boihng up to 103°, and the dimethylethynyl carbinol at 103-107° Discard the high boiling point material. Dry the fraction of low boihng point with anhydrous potassium carbonate and redistil. The total 3 ield is 75 g. 

The diluent gives the flavor a physical fixation. Relatively high boiling point materials are used in the diluent to make the flavor less heat labile. They are included when a flavor is to be used at temperatures above the boiling point of water examples include vegetable oils and isopropyl myristate. 

Maintain a Gas Phase Many catalytic chemical reactions used in processes today require both reactants and products to be in the gas phase. For high-boiling-point materials or operations... 

Obtain a Vapor Phase for Vapor-Liquid Equilibrium This situation arises quite frequently when high-boiling-point materials need to be distilled. An exanple is the distillation of crude oil in which the bottom of the atmospheric column is typically operated in the region of 310°C to 340°C (590°F to 645°F). 

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