Synthesis of 2-(4-hydroxyphenoxy)alkanoic acids
AssigneeHoechst Celanese Corporation
InventorsVaradaraj Elango, Kenneth G. Davenport
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Abstract
A method for synthesizing 2-(4-hydroxyphenoxy)alkanoic acids by reacting a hydroxyaromatic ketone derivative with a 2-substituted alkanoic acid under basic conditions and thereafter oxidizing the intermediate with subsequent hydrolysis.
Claims31
A method for synthesizing 2-(4-hydroxyphenoxy)alkanoic acids which comprises reacting a hydroxyaromatic ketone derivative (II) of the formula ##STR9## or a salt thereof;
- with a substituted acid of the formula ##STR10## under basic conditions to thereby form a 2-(acylphenoxy)alkanoic acid (III) of the formula ##STR11## and then oxidizing the thusly formed 2-(acylphenoxy)alkanoic acid with a peracid or peroxide to obtain an 2-(ayloxyphenoxy)alkanoic acid (IV) of the formula ##STR12## and then hydrolyzing or transesterifying said 2-(acyloxyphenoxy)alkanoic acid with a compound of the formula R.sup.2 OH/H.sup.+ to obtain a 2-(4-hydroxyphenoxy)alkanoic acid (V) of the formula ##STR13## wherein R is C.sub.1 to C.sub.18 alkyl or C.sub.6 to C.sub.10 aryl;
- and wherein R.sup.1 is H, phenyl or C.sub.1 to C.sub.18 alkyl;
- and wherein R.sup.2 is C.sub.1 to C.sub.18 alkyl, or aryl;
- and wherein A, B, C and D are independently H, X, CN, C.sub.1 to C.sub.18 alkyl, or C.sub.6 to C.sub.10 aryl;
- and X is F, Cl, Br, I or a sulfonic ester.
A method for synthesizing 2-(4-hydroxyphenoxy)alkanoic acids which comprises reacting a hydroxyaromatic ketone derivative (II) of the formula ##STR14## or a salt thereof;
- with a substituted ester of the formula ##STR15## under basic conditions to thereby form a 2-(acylphenoxy)alkanoic acid ester of the formula ##STR16## and then hydrolyzing the thusly formed 2-(acylphenoxy)alkanoic acid ester to form a 2-(acylphenoxy)alkanoic acid (III) of the formula ##STR17## and then oxidizing the thusly formed 2-(acylphenoxy)alkanoic acid with a peracid or peroxide to obtain a 2-(acyloxyphenoxy)alkanoic acid (IV) of the formula ##STR18## and then hydrolyzing or alcoholizing said 2-(acyloxyphenoxy)alkanoic acid with a compound of the formula R.sup.2 H.sup.+ to obtain a 2-(4-hydroxyphenoxy)alkanoic acid (V) of the formula ##STR19## wherein R is C.sub.1 to C.sub.18 alkyl or C.sub.6 to C.sub.10 aryl;
- and wherein R.sup.1 is H, phenyl or C.sub.1 to C.sub.18 alkyl;
- and wherein R.sup.2 and R.sup.3 are independently C.sub.1 to C.sub.18 alkyl, or aryl;
- and wherein A, B, C and D are independently H, X, CN, C.sub.1 to C.sub.18 alkyl, or C.sub.6 to C.sub.10 aryl;
- and X is F, Cl, Br, I or a sulfonic ester.
The compound 2-(4-acetoxyphenoxy)propanoic acid.
Dependencies are inferred from the claim text.