Unsubstituted dihydric phenols are alkylated with lower alkyl chlorides having a comparatively low reactivity in the presence of alkali metal carbonates or bicarbonates as a condensing agent. The reaction proceeds at moderate temperatures, and gives high yields of the monoalkylated phenols, ranging up to 98 percent, with dialkylation suppressed to below 3 percent. 12 Claims, No Drawings
Monomethylethers of an unsubstituted or symmetrically substituted dihydroxybenzene are prepared by reacting the dihydroxybenzene with methanol in the liquid phase at a temperature from 200.degree.C to 240.degree.C in the presence of boron phosphate as a catalyst.
2-(2-BUTYNYLOXY)-PHENOL AND A PROCESS FOR THE PRODUCTION OF THE SAME BY REACTING 2-HYDROXYACETOPHENONE AND A 2-HALOBUTYNE, OXIDIZING THE RESULTANT 2-(2-BUTYNYLOXY)-ACETOPHENONE AND HYDROLYZING THE 2-(2-BUTYNYLOXY)-PHENYL ACETATE OBTAINED.
A process for the preparation of a monoalkyl ether of a hydroxyphenol of the formula ##STR1## 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 ##STR2## with an alkyl halide, alkyl sulphonate or aryl sulphonate alkylating agent of the formula in which X is a halogen atom, or an alkylsulphonyloxy or arylsulphonyloxy radical, at a temperature from about 130.degree. C. to 200.degree. 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 C.sub.1-4 -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.
The process relates to the preparation of o-methallyloxyphenol by the action of methallyl chloride on pyrocatechol in the presence of a basic agent. It consists in carrying out the reaction in a two-phase liquid reaction medium comprising water and a water-immiscible organic solvent, at a temperature between 50.degree. and 140.degree. C., in the presence of a catalyst chosen from amongst quaternary ammonium derivatives and phosphonium derivatives, using, as the basic agent, an alkali metal or alkaline earth metal hydroxide or an alkali metal carbonate or bicarbonate. It makes it possible to obtain the monoether selectively by minimizing the formation of diether and of alkylation products of the benzene nucleus of the pyrocatechol.
A process for the isolation of a dihydroxybenzene-monoether from a reaction mixture containing solvent, ether and unreacted dihydroxybenzene, comprising contacting the reaction mixture with at least one hydrocarbon which is not miscible or only partially miscible with the reaction mixture, the ether selectively entering the hydrocarbon. Advantageously the reaction for the preparation of the monoether is carried out in an alcohol, a ketone, a dipolar aprotic solvent or a polyhydroxyalkyl ether, or a mixture thereof with water, the hydrocarbon used as extracting agent has a boiling point between about 80.degree. and 300.degree. C., and the extraction is carried out in the presence of water whereby there is an increase in the selectivity of the extraction.