Preparation process for hydroxyphenylacetic acids
AssigneeSociete Francaise Hoechst
InventorsJean-Claude Vallejos, Yani Christidis
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Abstract
Preparation process for a hydroxyphenylacetic acid of formula (I): ##STR1## where R.dbd.H, alkyl or alkoxyl as well as its salts, in which the corresponding free or salified hydroxymandelic acid of formula (II): ##STR2## in which R has the meaning given previously and M.dbd.H, K or an ammonium group is reacted in an aqueous medium, at a temperature greater than or equal to 50.degree. C., with formic acid in the presence of catalytic quantities of an oxygenated derivative of sulphur having a degree of oxidation from 2 to 4, in order to obtain the hydroxyphenylacetic acid of formula (I) which is isolated or, if desired, is salified according to the usual methods and the hydroxyphenylacetic acid thus obtained.
Claims19
Preparation process for a hydroxyphenylacetic acid of formula (I):
- ##STR5## in which R represents a hydrogen atom, a halogen atom or an alkyl or alkoxyl group as well as its salts, characterized in that the corresponding free or salified hydroxymandelic acid of formula (II):
- ##STR6## in which R has the meaning given previously and M represents a hydrogen, sodium, potassium atom or an ammonium group, is reacted in an aqueous medium, at a temperature greater than or equal to 50.degree. C., with formic acid in the presence of catalytic quantities of an oxygenated derivative of sulphur having a degree of oxidation from 2 to 4, in order to obtain the hydroxyphenylacetic acid of formula (I) which is isolated or, optionally, is salified.
Dependencies are inferred from the claim text.