Soda lime fusion

Carry out a preliminary soda lime fusion test to determine whether the base is liberated under these conditions if it is, repeat the experiment with 1 g. of the substance. Identify the base (amine) by its m.p. (if a solid) and the preparation of a solid derivative (Section IV,100). 

Long needles from cone. HHO3. M.p. 190° (195-6°). Sol. hot EtOH, hot cone. HNO3. Spar. sol. cold EtOH. Insol. HgO. Forms a ydride at 230°. Soda-lime fusion —y phosphoric acid -4- benzene. 

Upon warming with 10-20 per cent, sodium or potassium hydroxide solution, no ammonia is evolved (distinction from primary amides). The base, however, is usually liberated upon fusion with soda lime (see experimental details in Section IV,175) and at the same time the acyl group yields a hydrocarbon. Thus benz-p-toluidide affords p-tolu-idine and benzene. 

On boiling the methiodide with 70% sulfuric acid an N-methyl-oxo derivative was obtained, and this in turn gave 3-amino-2-phenyl-quinoline, methylamine, and ammonia on fusion with soda lime. The bulk of the evidence therefore favors quaternization at N-2 (cf, 154), in which case the acid-hydrolysis product is 155. Quaternization at N-2 would be expected because of the steric influence of the 10-phenyl group and the influence of the 4-amino group (cf. 4-hydroxy-pyridazine ) in the pyridazine-type ring, although the partial double-bond character of that ring is probably different from that in pyridazine itself. 

There are three straightforward tests which will provide useful information as to the general properties of the compound, and the presence of the more important of the elements noted above other than carbon, hydrogen and oxygen these tests are the ignition test heating with soda-lime and the sodium fusion test (Lassaigne s test). 

A number of nitrogen compounds, for example, proteins, do not yield cyanide ions easily with sodium fusion. It is advisable to perform the soda lime test for nitrogen if the sodium fusion shows absence of cyanide ion. 

E) Detection of Nitrogen. (1) Calcium Oxide Fusion. Mix 0.1 g of urea or casein with five times its bulk of pulverized soda lime. Place in a small evaporating dish, and cover with a watch glass, on the inner surface of which is laid a strip of moist red litmus paper. Now heat gently to avoid spattering, and observe the litmus paper. Allow the ignition mixture to cool, place a portion In a test tube, and test for sulfide ion. 

Chemical Test. Does the soda lime or the sodium fusion test (see Chapter 9) confirm the presence of nitrogen in your caffeine product ... 

Check the solubility of acetanilide in water. Is the aqueous solution acidic, basic, or does it remain neutral as indicated by pH paper Does the ignition test indicate that an aromatic group is present Does the soda lime or sodium fusion test indicate the presence of nitrogen Does the hydroxamate test for amides give a positive result ... 

Chemical Tests. Chemical classification tests (Chapter 9), such as the ignition test and the soda lime test (or sodium fusion test), may also be conducted to further establish the identity of the product. The hydroxamate test may be used to establish the presence of the amide functional group. 

In fusion reactions, pulverized mixtures are heated and usually the reactant in greater proportion melts completely and the binary reaction occurs then in the interface between a solid and a melt. Such interfacial reactions also occur between an excess of the solid reactant and minimal amounts of the fusible partner to give rise to a so-called ciypto fusion reaction. 2 An example is found in the behavior of lithium nitrate (m.p. circa 300 C) toward soda-lime glass. There is an exchange of sodium atoms of the sodium silicate for lithium atoms and the glass becomes dull. Since even slight quantities of lithium can bring about this effect, the latter may serve as a test for lithium. 

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