Patents by Inventor Andreas Dierdorf

Andreas Dierdorf has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5910605
    Abstract: The invention relates to a process for the preparation of 3-hydroxy-2-methylbenzoic acid and 3-acetoxy-2-methylbenzoic acid, which comprises reacting 3-chloro-2-methylphenol (3) with benzyl chloride to give 2-benzyloxy-6-chlorotoluene (4) subjecting this to a Grignard reaction with magnesium to give (3-benzyloxy-2-methylphenyl)magnesium chloride (5) reacting this with CO.sub.2 to give 3-benzyloxy-2-methylbenzoic acid (6) hydrogenating this or its alkali metal salts in the presence of a hydrogenation catalyst to give 3-hydroxy-2-methylbenzoic acid (2) and optionally acetylating this to give 3-acetoxy-2-methylbenzoic acid.
    Type: Grant
    Filed: February 6, 1998
    Date of Patent: June 8, 1999
    Assignee: Clariant GmbH
    Inventors: Robert Cosmo, Andreas Dierdorf
  • Patent number: 5811572
    Abstract: Process for the preparation of N-carboxymethyleneanthranilic acid esters of the formula (3) ##STR1## by reacting a compound of the formula (1) ##STR2## in which R' is hydrogen or a straight-chain or branched alkyl radical having 1 to 4 carbon atoms and R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are identical or different and independently of one another are hydrogen, halogen, NO.sub.2, a straight-chain or branched alkyl, alkoxy or halogenated alkyl radical having in each case 1 to 6 carbon atoms, with a glyoxylic acid ester of the formula (2)OHC--COOR (2)in which R is a straight-chain or branched alkyl radical having 1 to 20 carbon atoms, phenyl radical or benzyl radical, which are unsubstituted or mono- or polysubstituted by halogen or an alkyl or alkoxy group having in each case 1 to 4 carbon atoms, in the presence of a solvent at 0.degree. to 200.degree. C.
    Type: Grant
    Filed: February 7, 1997
    Date of Patent: September 22, 1998
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Theodor Papenfuhs, Andreas Dierdorf, Stefan Krause, Doris Neumann-Grimm
  • Patent number: 5712414
    Abstract: The present invention relates to a process for the preparation of hydroxycarboxylic acid amides of the general formula (1): ##STR1## in which R.sup.1 and R.sup.2 are identical or different and are hydrogen, halogen, cyano, a linear or branched alkyl, alkenyl, alkynyl or alkoxy group having 1 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a cycloalkyl group having 6 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, R.sup.3 is hydrogen or a linear or branched alkyl group having 1 to 4 carbon atoms, R.sup.4 is hydrogen or a linear or branched alkyl group having 1 to 6 carbon atoms, or R.sup.3 and R.sup.4, together with the carbon atom to which they are attached, form a five- or six-membered cycloalkane ring, and n is an integer from 1 to 12, wherein an aniline of the general formula (2) ##STR2## in which R.sup.1, R.sup.2, R.sup.3 and R.sup.
    Type: Grant
    Filed: July 10, 1996
    Date of Patent: January 27, 1998
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Andreas Dierdorf, Theodor Papenfuhs
  • Patent number: 5705680
    Abstract: The present invention relates to a process for the preparation of O-acylglycolanilides of the formula (1) ##STR1## in which R.sup.1 and R.sup.2 are identical or different and are hydrogen, halogen, a nitro group, a cyano group, a straight-chain or branched alkyl, alkenyl, alkynyl or alkoxy group having from 1 to 12 carbon atoms, an aralkyl group having from 7 to 12 carbon atoms, a cycloalkyl group having from 6 to 12 carbon atoms or an aryl group having from 6 to 12 carbon atoms,. R.sup.3 is hydrogen or a straight-chain or branched alkyl group having from 1 to 12 carbon atoms, and R.sup.4 is an alkyl group having from 1 to 6 carbon atoms or is a substituted or unsubstituted phenyl radical, in which an aniline of the formula (2) ##STR2## in which R.sup.1, R.sup.2 and R.sup.3 have the same meaning as in formula (1), and an O-acylglycolic acid of the general formula (3) ##STR3## in which R.sup.
    Type: Grant
    Filed: August 3, 1995
    Date of Patent: January 6, 1998
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Andreas Dierdorf, Theodor Papenfuhs
  • Patent number: 5693852
    Abstract: The present invention relates to a process for the preparation of O-acyloxycarboxanilides of the formula (I) ##STR1## in which R is a radical having 1 to 6 carbon atoms, n is an integer from 1 to 10, R.sup.1 is hydrogen or an alkyl radical having 1 to 12 carbon atoms, R.sup.2 and R.sup.3 are identical or different and are hydrogen, an alkyl radical having 1 to 12 carbon atoms, an aryl radical having 6 to 12 carbon atoms, a cycloalkyl radical having 5 to 12 carbon atoms in the ring, an alkenyl or alkynyl radical having 3 to 12 carbon atoms, NO.sub.2, F, Cl, Br or CN, by reacting a chlorocarboxanilide of the formula (II) ##STR2## in which n, R.sup.1, R.sup.2 and R.sup.3 have the abovementioned meaning, with an alkali metal carboxylate of the formula (III)R--COOMe (III),in which R has the abovementioned meaning and Me is an alkali metal, in the presence of an inert solvent and of a carboxylic acid having 1 to 6 carbon atoms, at 50.degree. to 200.degree. C.
    Type: Grant
    Filed: February 7, 1996
    Date of Patent: December 2, 1997
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Andreas Dierdorf, Theodor Papenfuhs, Siegfried Planker
  • Patent number: 5631403
    Abstract: The present invention relates to a process for the preparation of hydroxycarboxanilides of the formula (1) ##STR1## in which R.sup.1 and R.sup.2 are identical or different and are hydrogen, halogen, a nitro group, a cyano group, a straight-chain or branched alkyl, alkenyl, alkynyl or alkoxy group having 1 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, a cycloalkyl group having 6 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, R.sup.3 is hydrogen or a straight-chain or branched alkyl group having 1 to 12 carbon atoms and n is an integer from 1 to 12, by reacting a halocarboxanilide of the formula (2) ##STR2## in which R.sup.1, R.sup.2, R.sup.3 and n have the same meaning as in formula (1) and Hal is chlorine, bromine or iodine, with a basic compound in a solvent mixture comprising water and one or more polar aprotic solvents at a temperature of 40.degree. to 180.degree. C.
    Type: Grant
    Filed: June 21, 1995
    Date of Patent: May 20, 1997
    Assignee: Hoechst AG
    Inventors: Andreas Dierdorf, Siegfried Planker, Theodor Papenfuhs