Low-Temperature Baths for Maintaining

Loudness level, definition, 14-48 to 49 Low-Temperature Baths for Maintaining Constant Temperature, 15-35 Lumen, definition, 1-23 to 26 Lutetiumi see also Elements... 

In a 5-1, 3-necked flask fitted with a mechanical stirrer (Note 1), a dropping funnel, and a thermometer for reading low temperatures is placed 790 ml. (7 moles) of 48% h drobromic acid. The fl.ask and contents are cooled to 10-20 in an ice-salt bath, and 150 g, (1.59 moles) of 2-aminopyridine (Note 2) is added over a period of about 10 minutes. While the temperature is kept at 0° or lower, 240 ml. (4.7 moles) of bromine is added dropwise (Note 3). A solution of 275 g. (4 moles) of sodium nitrite in 400 ml. of water is added dropwise over a period of 2 hours, the temperature being carefully maintained at 0° or lower (Note 4). After an additional 30 minutes of stirring, a solution of 600 g. (15 moles) of sodium hydroxide in 600 ml. of water is added at such a rate that the temperature does not rise above 20-25° (Note 5). The nearly colorless reaction mixture is extracted with... 

Degradation of octaacetyllactobiononitrile. (Sodium ethoxide.y To 750 ml. of chloroform containing the impure octaacetyllactobiononitrile prepared from 200 g. of lactose, a solution of 15 g. of sodium in 750 ml. of methanol was added the solution was maintained at a low temperature and was shaken continuously. A jelly-like mass precipitated. When the precipitation was ended, 750 ml. of water and 50 ml. of acetic acid were added. The chloroform layer was separated and the water phase was evaporated in vacuo to a thick sirup. This was dissolved in 400 ml. of 96% ethanol, 65 g. of a,ai-benzylphenylhydrazine was added and the solution was heated in a water bath for thirty minutes. Assisted by seeding, crystallization of the hydrazone of the 3-( 9-D-galactopyranosyl)-D-arabinose was completed in five hours. The crystals were filtered and washed well with 80% ethanol yield 60-67 g., m. p. 223-225°. 

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