| 摘要 |
A process for the preparation of a monoalkyl ether of a hydroxyphenol of the formula <IMAGE> in which Z each independently is hydrogen or a substituent which is stable under the reaction conditions, R is lower alkyl, and n is 1, 2, 3 or 4, comprising reacting a hydroxyphenol of the formula <IMAGE> with an alkyl halide, alkyl sulphonate or aryl sulphonate alkylating agent of the formula R-X in which X is a halogen atom, or an alkylsulphonyloxy or arylsulphonyloxy radical, at a temperature from about 130 DEG C. to 200 DEG C. and in the presence of an alkali metal base or alkaline earth metal base and of a diluent comprising a polyhydroxyalkyl ether having at least one OH group. Advantageously the base is sodium carbonate, sodium bicarbonate, potassium carbonate or potassium bicarbonate, the hydroxyphenol is pyrocatechol, the alkylating agent is isopropyl chloride, isopropyl C1-4-alkyl-1-sulphonate, isopropyl benzenesulphonate or isopropyl tolyenesulphonate, and the polyhydroxyalkyl ether is glycol monomethyl ether, about 1.5 to 1.8 mols of alkylating agent and about 1 to 2 mols of the base being employed per mol of pyrocatechol, about 1.5 to 2.5 parts by weight of the glycol monomethyl ether being employed per part by weight of pyrocatechol, the reaction being effected in an inert atmosphere under elevated pressure. |
