Patents by Inventor Gunter Silber

Gunter Silber 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).

  • Process for the preparation of sodium salts of aromatic sulphinic acids containing nitro groups
    Patent number: 5359132
    Abstract: Sodium salts of aromatic sulphinic acids containing nitro groups are obtained in particularly pure form and good yield by introducing the corresponding sulphonyl chlorides into an aqueous alkali metal sulphite solution which is at a temperature of -10.degree. to 45.degree. C. and has a pH of 6 to 10, then cooling the suspension to -10.degree. to 0.degree. C., then metering in sodium hydroxide solution in such a way that the temperature does not exceed 0.degree. C. throughout the reaction, and then raising the temperature, maintaining stirring and simultaneously keeping the pH at 8 to 9 by the addition of sodium hydroxide solution.
    Type: Grant
    Filed: November 24, 1993
    Date of Patent: October 25, 1994
    Assignee: Bayer Aktiengesellschaft
    Inventors: Gunter Silber, Gerold Schade, Udo Thiel
  • Process for the preparation of .mu.-amino-acrylic acid esters
    Patent number: 5030747
    Abstract: .beta.-Amino-acrylic acid esters of the formula(R.sup.1 R.sup.2)NCH.dbd.CR.sup.3 --COOR.sup.4can be obtained by reaction of .beta.-hydroxy-acrylic acid ester alkali metal salts of the formulaMe.sup..sym. .crclbar. OCH.dbd.CR.sup.3 --COOR.sup.4with ammonium salts of the formula(R.sup.1 R.sup.2) NH.sub.2.sup..sym. .crclbar.according to the general reaction equation(R.sup.1 R.sup.2) NH.sub.2 X+MeOCH.dbd.CR.sup.3 --COOR.sup.4 .fwdarw.(R.sup.1 R.sup.2) NCH.dbd.CR.sup.3 --COOR.sup.4 +MeX.dbd.H.sub.2 OR.sup.1, R.sup.2, R.sup.3, R.sup.4, Me.sup..sym. and X.sup..crclbar. having the meaning indicated in the description and the reaction being carried out in an aprotic organic solvent, in which the reaction components are suspended, as the reaction medium and it being possible to replace a part of the aprotic organic solvent by a protic organic solvent which is miscible with the aprotic solvent to give a homogeneous phase.
    Type: Grant
    Filed: March 19, 1990
    Date of Patent: July 9, 1991
    Assignee: Bayer Aktiengesellschaft
    Inventors: Heinz U. Blank, Erich Wolters, Friedrich-Wilhelm Ullrich, Halmut Kraus, Gerhard Marzolph, Gunter Silber
  • Process for the preparation of optionally substituted 2-benzyl-toluenes
    Patent number: 4814483
    Abstract: Optionally substituted 2-benzyl-toluenes can be prepared by reaction of optionally substituted 2-benzyl-tert.-alkyl-toluenes with an optionally substituted aromatic hydrocarbon in the presence of anhydrous iron-(III) halide. The reaction is carried out at ambient to elevated temperature. The optionally substituted aromatic hydrocarbon is employed in molar excess, relative to the 2-benzly-tert.-alkyl-toluenes.
    Type: Grant
    Filed: December 12, 1986
    Date of Patent: March 21, 1989
    Assignee: Bayer Aktiengesellschaft
    Inventors: Heinz U. Blank, Gunter Silber