Process for preparing carboxylic acids by oxidation of aldehydes

• US 6,593,494 B2
• Filed: 03/28/2002
• Issued: 07/15/2003
• Est. Priority Date: 03/29/2001
• Status: Expired due to Fees

• Current Assignee: DSM Fine Chemicals Austria NFG GmbH & COKG (DSM-Firmenich AG)
• Original Assignee: DSM Fine Chemicals Austria NFG GmbH & COKG (DSM-Firmenich AG)
• Inventors: Schmieder Van De Vondervoort, Elisabeth, Alsters, Paul
• Primary Examiner(s): Rotman, Alan L.
• Assistant Examiner(s): OH, TAYLOR V
• Application Number:
  US10/107,429
• Publication Number:
  US 20020143206A1
• Time in Patent Office: 474 Days
• Field of Search: 562/418, 562/531
• US Class Current: 562/531
• CPC Class Codes: C07C 51/29 with halogen-containing compounds which may be formed in situ
• CPC Class Codes: C07C 59/64 containing six-membered aromatic rings

Abstract

Process for the oxidation of aldehydes to the corresponding acids in which an aldehyde as substrate is oxidized to the corresponding acid in the presence of an equimolar amount, or a molar excess, of periodate, catalytic amounts of dichromate or CrO₃, and in the presence of an acid in water, a water/solvent mixture or in a solvent at a temperature of −20° C. to +50° C.

Claims

1. A process for the oxidation of aldehydes of the formula I

where R is an unbranched, branched or cyclic, unsubstituted or substituted C₁-C₂₀-alkyl radical, an aryl radical to the corresponding acids, which comprises oxidizing the aldehyde, as a substrate, to the corresponding acid in the presence of an equimolar amount, or a molar excess, of periodate, catalytic amounts of dichromate or CrO₃, and in the presence of an acid selected from the group consisting of sulfuric acid, HCl, HNO₃, p-toluenesulfonic acid, HBF₄, H₅IO₆, CF₃SO₃H or perfluorotetradecanoic acid or mixtures thereof, in water, a water/solvent mixture or in a solvent, the solvent being selected from the group consisting of toluene, chloroform, dichloromethane, ethyl acetate, diethyl ether, methyl t-butyl ether, dimethoxyethane, 2-methoxyethyl ether, triethylene glycol dimethyl ether, dioxane, THF, acetone, isopropyl acetate and acetonitrile, at a temperature of from −

20°

C. to +50°

C.

2. The process as claimed in claim 1, wherein the aldehydes are compounds of the formula I where R is an unbranched or branched C₁-C₂₀-alkyl radical which is unsubstituted or substituted by halogen, C₁-C₈-alkoxy, aryloxy or phenyl which is unsubstituted or substituted with C₁-C₁₂-alkyl, halogen, C₁-C₈-alkoxy or aryloxy.

3. The process as claimed in claim 1, wherein the aldehydes are compounds of the formula I where R is an unbranched or branched C₁-C₂-alkyl radical which is substituted by a phenyl which is monosubstituted or disubstituted by C₁-C₄-alkyl, C₁-C₄-alkoxy, phenoxy, fluorine or chlorine.

4. The process as claimed in claim 1, wherein from 1.1 to 10 molar equivalents of periodate are added.

5. The process as claimed in claim 1, wherein periodate is used in the form of the Na, K or Bu₄N salt.

6. The process as claimed in claim 1, wherein dichromate or CrO₃ is added in amounts of from 0.1 to 20 mol % based on the aldehyde.

7. The process as claimed in claim 1, wherein an amount of acid corresponding to 1-30 mol % H⁺, based on the substrate is used.