Bayer Corporation

Bayer Cropscience Gmbh

Bayer Cropscience Ag

Joe J Hanson

Klaus Jelich

Vidyanatha A Prasad

Shekhar Kulkarni

Klaus Stroech

Dennis E Jackman

David M Mayes

Shekhar V Kulkarni

The present invention provides a method of preparing 1-acetyl-1-chlorocyclopropane from 1,3 dichloro-2-pentanone by reaction with base in the presence of a phase transfer catalyst. The reaction may be run in the presence or absence of an organic solvent and in a continuous or batch process.

Method of preparing 1-acetyl-1-chlorocyclopropane

The present invention relates to a method for the preparation of as 1-(4-Chlorophenyl)-4,4-dimethylpent-1-ene-3-one, also known as Phenyl aldol. The process of the present invention utilizes catalysts. The process enables the manufacture of the Phenyl aldol in the absence of a solvent and without crystalization or filtration steps. Yields in the range of about greater than 95% with purities in the range of about greater than 95% have been obtained with the present invention.

Process for the preparation of 1-(4-chlorophenyl)-4,4-dimethylpent-1-ene-3-one

Methods of purifying 2-methylthio-5-trifluoromethyl-1,3,4-thiadiazole include the steps of providing a first 2-methylthio-5-trifluoromethyl-1,3,4-thiadiazole composition comprising 2-methylthio-5-trifluoromethyl-1,3,4-thiadiazole and organic solvent; performing a first extraction of the 2-methylthio-5-trifluoromethyl-1,3,4-thiadiazole composition with a first inorganic acid solution; and performing a second extraction of the 2-methylthio-5-trifluoromethyl-1,3,4-thiadiazole composition with a second inorganic acid solution.

Methods of purifying 2-methylthio-5-trifluoromethyl-1,3,4-thiadiazole

The present invention provides a process for making thiadiazole sulfones. In particular, the present process is used to make 2-(methylsulfonyl)-5-(trifluoromethyl)-1,3,4-thiadiazole using catalytic oxidation in the presence of a suitable oxidizing agent. The catalyst system used for the oxidation reaction is a mixture of glacial acetic acid and a tungsten catalyst. The tungsten catalyst is preferably selected from the group consisting of sodium tungstate, potassium tunstate, and tungstic acid.

Process for the preparation of

The present invention provides a process for making thiadiazole sulfones. In particular, the present process is used to make 2-(methyl-sulfonyl)-5-(trifluoromethyl)-1,3,4-thiadiazole using catalytic oxidation in the presence of a suitable oxidizing agent. A preferred oxidizing agent is hydrogen peroxide. The catalyst system used for the oxidation reaction is a mixture of boric acid and glacial acetic acid. The molar ratio of glacial acetic acid to 2-(methylthio)-5-(trifluoromethyl)-1,3,4-thiadiazole is from about 0.1:1 to about 0.5:1.

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Holt, MO, United States of America

Joe J Hanson