1-Naphthol experimental procedures

Calmagite. This indicator, l-(l-hydroxyl-4-methyl-2-phenylazo)-2-naphthol-4-sulphonic acid, has the same colour change as solochrome black, but the colour change is somewhat clearer and sharper. An important advantage is that aqueous solutions of the indicator are stable almost indefinitely. It may be substituted for solochrome black without change in the experimental procedures for the titration of calcium plus magnesium (see Sections 10.54 and 10.62). Calmagite functions as an acid-base indicator ... 

Experimental Procedure 2.2.3. Benzannulation with a Chromium Phenylcar-hene Complex [ 1 -4 4a,8a-Ti -2-(r rr-Butyl)-4-methoxy-1 -naphthol]tricarbonyl-chromium [37, p 140]... 

In the experimental procedures that follow, three types of separations of neutral, acidic, and basic compounds are described. The first involves separating a mixture of benzoic acid (5) and naphthalene (7), using aqueous hydroxide for the extraction. The flow chart for this separation corresponds to that of Figure 5.1. The second procedure involves separating a mixture of 5,7, and 2-naphthol (11). In this case, 5 is first selectively removed from the solution by extraction with aqueous bicarbonate, which does not deprotonate 11. A second basic extraction using aqueous hydroxide removes 11 from the organic solution. The flow chart for this sequence is depicted in Figure 5.3. 

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