Bayer Aktiengesellschaft

Volker Glock

Hans-Josef Buysch

Rolf-Volker Meyer

Wolfgang Ebert

Eberhard Zirngiebl

Lutz Heuer

Heinz-Joachim Rother

Joachim Komoschinski

Ursula Pentling

Joerg-Dietrich Jentsch

Willi Streicher

Friedrich-Wilhelm Ullrich

Bernd Griehsel

Horst Koller

Bernd Pennemann

Method for preparing 2-nitro-5-(phenylthio)-anilines

For the continuous preparation of 6-oxo-(6H)-dibenz-�c,e!�1,2!-oxaphosphorins (ODOPs), 6-chloro-(6H)-dibenz-�c,e!�1,2!-oxaphosphorins (CDOPs) are continuously reacted with at least the stochiometrically required amount of water at elevated temperature in a reaction section having little backmixing.

Process for preparing 6-oxo-(6H)-dibenz-�C,E! �1,2!-oxaphosphorins

The present invention relates to an-economically and ecologically advantageous process, which is easy to carry out, for the preparation of specific polyethylene glycol diesters of 2-(4-chloro-2-methylphenoxy)-propionic acid, and to the substance mixture obtainable by this process and the use thereof as a root penetration inhibitor in building materials and insulating compositions, such as, for example, bitumen.

Process for the preparation of specific polyethylene glycol di

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)

New hydrated niobium oxide and hydrated tantalum oxide catalysts containing pores having diameters in the range from 0.4 to 10,000 nm are characterized in that the volume of the pores of the catalyst having a diameter of from 100 to 1000 nm is at least 30% of the total pore volume of the catalyst. The catalysts can be prepared by mixing hydrated niobium oxide or hydrated tantalum oxide with an inert solid and converting this mixture into a solid pellet form, with the pressure in the apparatus for preparing catalysts in pellet form being set in such a way that the volume of the pores of the catalyst having a diameter of from 100 to 1000 nm is at least 30% of the total pore volume of the catalyst. Such catalysts are particularly suitable for preparing N-alkylanilines from anilines and alkanols.

Hydrated niobium oxide and hydrated tantalum oxide catalysts, their

This invention relates to a process for the preparation of high molecular weight, optionally branched polyarylenesulphides from alkali metal sulphides, optionally in admixture with alkali metal hydrogen sulphides and aromatic dihalogen compounds, in a polar solvent in the presence of from 0.1 to 6.0 mol-%, preferably from 0.25 to 4.0 mol-%, of an aromatic monoalkoxy or monoalkylthio compound. The polyarylenesulphides obtained have reproducibly adjustable melt viscosities and molecular weights and are distinguished by their reduced tendency to corrosion.

Process for the preparation of high molecular weight optionally branched

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Krefeld, Germany

Volker Glock