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Apparatus Hershberg stirrer

In a 1-1. three-necked round-bottomed flask equipped with a Hershberg stirrer, a thermometer, and a 250-ml. dropping funnel are placed 80 g. (0.666 mole) of acetophenone, 60 ml. of ether, and 100 ml. of water. The apparatus is assembled in a well-ventilated hood, the flask is surrounded by an ice-salt bath, and 82 g. (1.67 moles) of granulated sodium cyanide is added all at once with vigorous stirring. When most of the sodium cyanide has dissolved and the temperature of the mixture has fallen to 5°, 140 ml. (1.7 moles) of concentrated hydrochloric acid is... [Pg.64]

The experimental conditions for conducting the above reaction in the presence of dimethylformamide as a solvent are as follows. In a 250 ml. three-necked flask, equipped with a reflux condenser and a tantalum wire Hershberg-type stirrer, place 20 g. of o-chloronitrobenzene and 100 ml. of diinethylform-amide (dried over anhydrous calcium sulphate). Heat the solution to reflux and add 20 g. of activated copper bronze in one portion. Heat under reflux for 4 hours, add another 20 g. portion of copper powder, and continue refluxing for a second 4-hour period. Allow to cool, pour the reaction mixture into 2 litres of water, and filter with suction. Extract the solids with three 200 ml. portions of boiling ethanol alternatively, use 300 ml. of ethanol in a Soxhlet apparatus. Isolate the 2 2- dinitrodiphenyl from the alcoholic extracts as described above the 3ueld of product, m.p. 124-125°, is 11 - 5 g. [Pg.528]

The apparatus consists of a 3-1. three-necked round-bottomed creased flask, with standard ball joints and an indented cone-shaped bottom (Note 1), which is heated by means of an electric mantle and is equipped with a high-speecT stirrer of stainless steel driven by a 10,000 r.p.m. motor (Note 2). One side neck is fitted with a bulb-type air-cooled condenser (Note 3), on top of which fits a 1-1. pressure-equalizing Hershberg dropping funnel (Note 4). The top of the dropping funnel is to be connected in turn to a U-tube containing a 1-cm. head of mercury. The entire apparatus is securely fastened to a sturdy support. [Pg.79]


See other pages where Apparatus Hershberg stirrer is mentioned: [Pg.936]    [Pg.421]    [Pg.936]    [Pg.936]    [Pg.617]    [Pg.1180]    [Pg.617]    [Pg.31]    [Pg.100]    [Pg.941]    [Pg.936]    [Pg.51]    [Pg.80]    [Pg.936]    [Pg.421]    [Pg.421]    [Pg.1319]    [Pg.20]    [Pg.897]    [Pg.922]    [Pg.897]    [Pg.922]    [Pg.897]    [Pg.922]    [Pg.118]    [Pg.118]    [Pg.897]    [Pg.922]    [Pg.897]    [Pg.922]   
See also in sourсe #XX -- [ Pg.17 , Pg.31 ]

See also in sourсe #XX -- [ Pg.15 , Pg.17 , Pg.18 , Pg.31 , Pg.73 ]




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