DE638824C - Process for the preparation of oxyarylcarboxylic acid esters - Google Patents

Description

The subject of the main patent 638 072 is the implementation of mono- or polyoxyarylcarboxylic acid chlorides or their derivatives esterified in the hydroxyl group with the salts of monooxyaryl-, -alkyl-, -cycloalkyl- or aralkylsulfonic acids or their derivatives. The carboxyl group is the Oxyarylcarboxylic acids esterified by the hydroxyl group of the oxysulfonic acids.

ίο It has now been shown that one is in place of the monooxysulfonic acids also include polyoxyaryl, alkyl, cycloalkyl or aralkyl sulfonic acids saturated or unsaturated type can use. Depending on the proportion of the The esterification takes place either on one or on several or all hydroxyl groups of the polyoxysulfonic acids instead. Esterification can also be carried out in stages.

The possibility of producing such multiply esterified compounds is important insofar as this leads to water-soluble products in which the labile-bound oxyarylcarboxylic acids are enriched to an extremely high degree. Products, such as tri- (tetrao-oxybenzoyl) -pyrogallolsulfonsäuren, capable in their disintegration to provide 100.6 ° / ₀ effective salicylic acid, and also such products have the typical properties of the produced according to the main patent substances in an excellent way.

example 1

² 7> 7 S ° ■ Oxybenzoyl - ο - oxybenzoic acid chloride, dissolved in 40 ecm benzene, are mixed with a solution of 9.5 g resorcinol sulfonic acid and 6.0 g sodium hydroxide in 200 ecm water and shaken well for 1 hour while cooling. After the benzene layer has been separated off, the aqueous solution of the sodium salt of the condensation product, from which the sulfonic acid is obtained, is obtained

(HO-C ₆ H ₄ -CO-OC ₆ H ₄ -CO-O) ₂ -C ₆ H ₃ -SO ₃ H can be deposited as a water-containing, thick, colorless oil by acidification with strong hydrochloric acid. The oil is very easily soluble in water.

Example 2

27.7 g of the o-oxybenzoyl-o-oxybenzoic acid chloride are dissolved in 200 ecm of benzene by gentle heating and in a solution of 19 g resorcinol sulfonic acid in 500 ecm

*) The patent seeker stated as the inventor:

Dr. Walter Maier in Jeßnitz, Anh.

Water, which also contains 20 g of magnesium oxide in a suspended form, entered. With vigorous stirring, an emulsion-like mixture forms. After 2 hours the excess. Magnesr
oxide filtered off and the filtrate in the Scheii
funnel freed from the benzene layer.-The aqueous layer contains the o-oxybenzoylo-oxybenzoylresorcinol sulfonic acid

HO-C ₈ H ₄ -CO-OC ₆ H ₄ -CO-OC ₈ H ₃ - (OH) -SO ₃ H in the form of the easily soluble magnesium salt. Example 3

55 S of the condensation product of salicylic acid and phosphorus trichloride are dissolved in 200 ecm of ether, and this solution is dissolved in an aqueous solution of 28 g of pyrogallol sulfonic acid, which also contains 30 g of Ma

contains magnesium oxide. A mixture of the single, double and triple esterification products is produced, but mainly ψ double esterification products.

Claims (1)

Claim: Process for the preparation of oxyarylearboxylic acid esters according to patent 638 072, characterized by ^ that one here the Hydroxyl groups of polyoxyaryl, alkyl, cycloalkyl or aralkyl sulfonic acids, where the alkyl radicals can also be of higher molecular weight, in aqueous solution with the mono- or polyoxyarylcarboxylic acid chlorides mentioned in the main patent or their esterification in the hydroxyl group derivatives obtained in stages or in one go, fully or only partially esterified.