Bayer Aktiengesellschaft

Lanxess Deutschland Gmbh

Saltigo Gmbh

Bernd Griehsel

Andreas Sattler

Andreas Job

Hans-Josef Buysch

Dieter Freitag

Helmut Waldmann

Claus H Wulff

Uwe Westeppe

Guido Steffan

Carl Casser

Manfred Hajek

Klaus D Berg

Alfred Eitel

Karsten Von Dem Bruch

Joachim Komoschinski

Volker Glock

G&uuml;nter Rauchschwalbe

Johannes Scherer

The present invention relates to an improved process for preparing N,N'-carbonyldiazoles by reacting azoles with phosgene.

Method for the production of N,N-carbonyldiazoles

A process is provided for preparing N,N'-carbonyldiazoles by reacting azoles with phosgene in halogenated aliphatic hydrocarbon solvents, the entirety of the azole for reaction being introduced in the solvent, followed by the addition of phosgene.

Process for preparing N,N'-carbonyldiazoles

Method for the production of 2,6-dichloro-5-fluoro-nicotinic acid and coarse and particularly pure 2,6-dichloro-5-fluoro-nicotinic acid

The process according to the invention can be illustrated by way of example by the following equation:

Method for the production of 2,6-dichloro-5-fluoronicotinonitrile and the chemical compound 3-cyano-2-hydroxy-5-fluoropyride-6-one-monosodium salt its tautomers

Optionally substituted ODOP is obtained by reaction of optionally substituted o-phenylphenol with PCl.sub.3 in the presence of Lewis acids at elevated temperature in a first stage, with according to the invention an excess of at least 0.05 mol of PCl.sub.3 per mol of o-phenylphenol being maintained during the entire reaction time, and, after removal of the PCl.sub.3, by hydrolysis in a second stage using 1-2 mol of H.sub.2 O per chlorine equivalent of the product of the first stage at 50.degree.-150.degree. C. and with removal of HCl and residual H.sub.2 O.

Process for preparing 6-oxo-(6H)-dibenz-[c,e][1,2]-oxaphosphorins (ODOPs)

This invention relates to a process for the preparation of substituted cycloalkylidene bisphenols from phenols and special cycloalkanones in the presence of acid condensation catalysts and in the presence of water.

Process for the preparation of substituted cycloalkylidene bisphenols

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Bottrop, Germany

Bernd Griehsel