Ketocarboxylic acids, methods of manufacture and uses thereof
AssigneeSegetis, Inc.
InventorsBrian D. Mullen, Cora M. Leibig, Leo E. Manzer
Life of this patent
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Abstract
Ketocarboxylic acids such as levulinic acid can be efficiently purified in high yield by esterification with a hydrocarbon polyol to the corresponding polyketocarboxylic ester, which can be readily purified, for example recrystallized. After purification, the ketocarboxylic ester can be hydrolyzed to provide pure ketocarboxylic acid, or a salt thereof, after removal of the esterifying hydrocarbon polyol, or used for other synthetic transformations. Advantageously, the polyketocarboxylic esters, ketocarboxylic acids, and salts thereof produced by this method are obtained in high purity.
Claims35
A method for reducing a content of an impurity in a ketocarboxylic acid composition comprising at least 1 wt % of the impurity and a ketocarboxylic acid I
- wherein
- R2 is C1-C6 alkyl and
- a=0-3,
- the method comprising:
- contacting a hydrocarbon polyol II
- G-[OH]t II
- wherein
- G is a hydrocarbyl group having a valence oft, and
- t=2-3,
- with the ketocarboxylic acid composition in an esterification reaction mixture wherein the ketocarboxylic acid I is present in an amount of at least 0.75 equivalents of the ketocarboxylic acid I per one equivalent of hydroxy group in the hydrocarbon polyol II, under conditions effective to form a ketocarboxylic ester III
- wherein
- R2 is C1-C6 alkyl,
- a=0-3,
- y=2-3 and z=0-1, provided that z+y=t;
- and
- isolating the ketocarboxylic ester III from the esterification reaction mixture.
A method for the purification of a composition comprising ketocarboxylic acid I and an impurity,
- wherein
- R2 is C1-C6 alkyl and
- a=0-3,
- the method comprising:
- esterifying a hydrocarbon polyol II with a composition comprising a ketocarboxylic acid I and an impurity in an esterification reaction mixture, wherein the ketocarboxylic acid I is present in an amount of at least 0.75 equivalents of the ketocarboxylic acid I per one equivalent of hydroxy group in the hydrocarbon polyol II
- G-[OH]t II
- wherein
- G is ethylene, n-propylene, n-butylene, or n-hexylene, and
- t=2,
- to form a ketocarboxylic ester III
- wherein
- R2 is C1-C6 alkyl,
- a=0-3,
- y=2-3 and z=0-1, provided that z+y=t;
- isolating the polyketocarboxy ester III from the esterification reaction mixture, and decomposing the isolated polyketocarboxylic acid ester III to provide the purified ketocarboxylic acid I composition or a salt thereof.
Dependencies are inferred from the claim text.