Bayer Aktiengesellschaft

Bernd-Michael Konig

Torsten Groth

Josef Kasbauer

Herbert Eichenauer

Heinz U Blank

Karl-Erwin Piejko

Helmut Judat

Alexander Klausener

Paul Wagner

Michael Schwamborn

Heinz-Ulrich Blank

Frank Dobert

3-Methoxy-1-propanol is prepared in an advantageous manner by alkylating 1,3-propanediol with methyl chloride in the presence of a base.

Process for preparing 3-methoxy-1-propanol

Thermoplastics built up from N-(2-ethyl-6-methyl)phenylmaleimide and styrene, it being possible for all or some of the styrene to be replaced by at least one other monomer component.

Thermoplastics having a high heat deflection temperature and improved

Mononitrohalogenobenzenes can be prepared by mixing halogenobenzene, nitric acid, sulphuric acid and water intensively with one another, simultaneously or in succession in their total quantity, and by redispersing them at least twice in the case of continuous preparation, applying a mixing energy of 1-40 watts per liter of the overall reaction mixture, preferably 3-30 W/l, largely suppressing back-mixing in the continuous procedure, and observing adiabatic reaction conditions.

Process for the adiabatic preparation of mononitrohalogenobenzenes

A process for the preparation of a N-)ortho-alkylphenyl)-imide of the formula ##STR1## in which R.sup.1 to R.sup.9 is defined in the specification which comprises reacting a cyclic anhydride of the formula ##STR2## wherein R.sup.6 to R.sup.9 are difined in the specification with an amine of the formula ##STR3## optionally in the presence of an acid catalyst and optionally in the presence of a solvent which is immiscible or only slightly miscible with water but can form an azeotrope with water, at a temperature between 100.degree. to 200.degree. C. under conditions so that the water formed during the reaction is removed from the reaction mixture without the addition of a polymerization inhibitor or a dipolar solvent. The final products are used as intermediates to prepare heat-stable plastics as well as intermediates to prepare pharmaceutical and agricultural chemicals.

Process for the preparation of N-(ortho-alkylphenyl)-imides

Mononitrotoluenes can be prepared by intensively mixing together toluene, nitric acid, sulphuric acid and water, simultaneously or successively in their total amount, and, in the case of continuous preparation, redispersing the mixture at least twice, for which purpose a mixing energy of 1 to 40 watts per liter of the total reaction mixture, preferably 3 to 30 W/l, is employed per volume of the reactor, and, for the continuous procedure, the back mixing is substantially repressed. Adiabatic reaction conditions are maintained.

Process for the adiabatic preparation of mononitrotoluenes

Dinitro-polyalkylbenzenes can be prepared by nitration of polyalkylbenzenes using HNO.sub.3 in the presence of H.sub.2 SO.sub.4 in such a manner that at least 50% of the H.sub.2 SO.sub.4 is present as reaction medium and HNO.sub.3 and the polyalkylbenzene and any remaining H.sub.2 SO.sub.4 are added simultaneously in such a manner that the added substances polyalkylbenzene and HNO.sub.3 are in the molar ratio of 1:2-10. H.sub.2 SO.sub.4 is used at a concentration from 81 to 96% by weight and HNO.sub.3 at a concentration from 95 to 100% by weight. For the work-up, the dinitro-polyalkylbenzenes are first freed from the majority of the acids and then treated with a highly dilute aqueous solution of a dispersant for separating off residual acid.

Growing community of inventors

Bergisch Gladbach, Germany

Bernd-Michael Konig