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There are numerous references in the literature to the synthesis of various halophenoxyethanols, or ethylene glycol halophenyl ethers, by the reaction of sodium halophenates with ethylene chlorohydrin (1-4). The corresponding esters have also been reported, including acetates, methacrylates, crotonates, maleates, and cinnamates (4-7).Another procedure used less frequently for the synthesis of halophenoxyethanols involves the condensation of halophenols with ethylene oxide (3, 5). By this method 2-(pentachlorophenoxyethoxy) ethanol and 2-(pentachlorophenoxyethoxyethoxy)ethanol, the analogous derivatives of diethylene glycol and triethylene glycol, respectively, were prepared. In one instance 2-(2,4-dichlorophenoxyethoxy)ethanol was made by the reaction of sodium 2,4-dichlorophenate with diethylene glycol chlorohydrin (8). The acetates of these compounds have also been reported (9). This paper is concerned with the synthesis of chlorophenoxyethoxyethanols and chlorophenoxyethoxyethoxyethanols by the condensation of polychlorobenzenes with diethylene glycol and triethylene glycol, respectively, in the presence of sodium hydroxide and an excess of the glycol.The hydrolysis of 1,2,4,5-tetrachlorobenzene with sodium hydroxide in solution of methanol at 160°in an autoclave (10) yields 2,4,5-trichlorophenol. This phenol is also formed from 1,2,4,5-tetrachlorobenzene when ethylene glycol and propylene glycol are used as solvents at 170-200°at atmospheric pressure (11).Investigation of this reaction using diethylene glycol as solvent at 200°g ave 2,4,5-trichlorophenol (I) as the major product, and a small amount (5 %) of an oil obtained as a steam-distillation residue. Lower reaction temperatures favored the formation of an intermediate compound, 2-(2,4,5-trichlorophenoxyethoxy)ethanol (II). At 125°u sing 1,2,4,5-tetrachlorobenzene and sodium hydroxide in a molar ratio of 1 to 2.5, the maximum alkali consumption was 1.1 moles as determined by titration of hydroxyl ion during the course of the reaction. Onetenth mole of 2,4,5-trichlorophenol was isolated from the reaction mixture corresponding to a yield of 10%. This was subsequently confirmed in a larger scale experiment, in which an 11 % yield of the phenol and 72.5% of 2-(2,4,5trichlorophenoxyethoxy) ethanol were obtained. This compound was esterified with acetic anhydride to give 2-(2,4,5-trichlorophenoxyethoxy) ethyl acetate (III) in 91.6% yield.

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The rates of reaction of catechol with several acyl halides were determined in 95% acetone. The results indicate that the reaction proceeds by a concerted attack of the monocatecholate ion on the acyl halide with the formation of the monoacyl ester of catechol. Benzenesulfonyl fluoride and benzoic anhydride appear to react with catechol by a similar concerted mechanism. Resorcinol, hydroquinone and phenol are, relative to catechol, unreactive toward acyl halides.

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