Patents by Inventor Gunther Semler

Gunther Semler 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: 5349104
    Abstract: Without added stabilizers, aminobenzotrifluorides have low thermal and storage stability.The present invention relates to preparations of a stabilized amionbenzotrifluoride, composed essentially ofa) an aminobenzotrifluoride of the formula (I), ##STR1## in which R.sup.1 and R.sup.2, independently of each other, are hydrogen, C.sub.1 -C.sub.6 -alkyl, C.sub.2 -C.sub.6 -alkenyl, substituted or unsubstituted aryl, halogen, CF.sub.3, nitro, amino, methoxy, hydroxyl or NR.sup.3 R.sup.4, where R.sup.3 and R.sup.4, independently of each other, are hydrogen or C.sub.1 -C.sub.5 -alkyl radicals, and the NH.sub.2 group can be located in the 2-, 3- or 4-position in relation to the CF.sub.3 group, andb) at least one base.
    Type: Grant
    Filed: May 4, 1993
    Date of Patent: September 20, 1994
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Gilbert Billeb, Gunther Semler
  • Patent number: 5241120
    Abstract: Process for the preparation of alkyl 3-chlorophenyl sulfones of the formula (I), in which R.sub.1 and R.sub.2 are straight-chain or branched alkyl (C.sub.1 -C.sub.4) groups, which can be identical or different, by reacting alkyl phenyl sulfones of the formula (II), in which R.sub.1 and R.sub.2 have the meanings given above, with chlorine in sulfuric acid or fuming sulfuric acid at temperatures of about 20 to about 180.degree. C.
    Type: Grant
    Filed: June 15, 1992
    Date of Patent: August 31, 1993
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Gunther Sell, Gunther Semler
  • Patent number: 5003079
    Abstract: Process for the preparation of benzimidazolones of the formula (1) ##STR1## in which R.sub.1 and R.sub.2 are identical or different and denote hydrogen or halogen atoms, or alkyl(C.sub.1 -C.sub.4), alkoxy(c.sub.1 -C.sub.4), trifluoromethyl, phenyl, phenoxy or nitro groups, by reacting o-phenylenediamines of the formula (2) ##STR2## in which R.sub.1 and R.sub.2 have the meaning given, with phosgene in water in the presence of an alkali metal base or alkaline earth metal base or a salt of an alkali metal hydroxide or alkaline earth metal hydroxide and a weakly inorganic or organic acid or a mixture of such salts or a suitable buffer system, at a pH of about 6 to about 12, and at a temperature of about 20.degree. to 100.degree. C.
    Type: Grant
    Filed: November 24, 1989
    Date of Patent: March 26, 1991
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Michael Meier, Gunther Semler
  • Patent number: 4770820
    Abstract: Carbamoyl chlorides derived from secondary aliphatic amines having alkyl groups which are branched in the 1-position are prepared by passing phosgene at an elevated temperature into the corresponding, initially taken--if appropriate dissolved in an inert solvent--secondary aliphatic amines having alkyl groups which are branched in the 1-position.The reaction products are intermediates in various specialized fields, particularly in the plant protection sector.
    Type: Grant
    Filed: April 14, 1986
    Date of Patent: September 13, 1988
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Gunther Semler, Georg Schaeffer
  • Patent number: 4340746
    Abstract: Thiochloroformates are prepared by reaction of mercaptans with phosgene in the presence of carboxylic acid amides and/or urea derivatives as catalysts in amounts smaller than hitherto known for this application. The amounts range from about 0.02 to 0.2 mol %, relative to the corresponding starting mercaptan. Despite the small amounts of catalyst the reaction proceeds as with the use of larger catalyst amounts; however, work-up is simplified and the product yields are increased in most cases.
    Type: Grant
    Filed: August 26, 1980
    Date of Patent: July 20, 1982
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Gunther Semler, Georg Schaeffer
  • Patent number: 4085129
    Abstract: A process for the preparation of chloroformic acid aryl-esters and cyclic carbonates of aryl compounds containing at least two phenolic hydroxy groups wherein aromatic compounds containing one or more hydroxy groups linked to an aromatic nucleus, are reacted with phosgene in the presence of catalytic amounts of N,N-disubstituted acid amide either under pressure or without pressure while removing the hydrogen chloride continuously from the reaction mixture. This improved process results in almost quantitative or very high yields of pure products and avoids problems such as disposal of waste water.
    Type: Grant
    Filed: September 28, 1976
    Date of Patent: April 18, 1978
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Gunther Semler, Georg Schaeffer
  • Patent number: 3962326
    Abstract: Process for preparing carboxylic acid chlorides by reaction of carboxylic acids or carboxylic anhydrides with phosgene at temperatures of from 0.degree. to 180.degree.C in the presence of a catalyst, wherein 0.01 to 10 weight percent, calculated on the carboxylic acid or the carboxylic anhydride, of trisubstituted phosphine oxides or trisubstituted phosphine sulfides or reaction products of these compounds with phosgene and/or acids or acid anhydrides or mixtures of these compounds are used as catalyst.
    Type: Grant
    Filed: April 24, 1974
    Date of Patent: June 8, 1976
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Gunther Semler, Georg Schaeffer, Karl Waldmann