反应详情

In step (a), β-naphthol is preferably first added to an aqueous alcoholic alkaline medium, for instance a solution of an alkali metal hydroxide in a mixture of water and a C1-C4 aliphatic alcohol, especially methanol or ethanol, at an elevated temperature preferably at a temperature within the range of 70°-100° C. To the resulting pale brown emulsion, the chloroform reactant is then added slowly -- preferably dropwise -- at an elevated temperature, preferably 70°-100° C. After the addition of a few drops of chloroform, the reaction mixture assumes a blue colouration which is allowed to change to green before any further chloroform is added. Subsequently, chloroform is added slowly and at such a rate that the green colouration is maintained. After completion of the addition of chloroform, the alkali metal salt of 2-hydroxy-1-naphthaldehyde may be isolated e.g. by filtration, and washed, preferably with brine.

1. customwithin the range of 70°-100° C
2. customat an elevated temperature, preferably 70°-100° C
3. additionis added
4. temperatureat such a rate that the green colouration is maintained