Bayer Aktiengesellschaft

Lanxess Deutschland Gmbh

Dieter Irmscher

Wolfgang Podszun

Heinz U Blank

Wolfgang Zarges

Karlheinrich Meisel

Willi Streicher

Friedrich-Wilhelm Ullrich

Michael Happ

Gunther Klag

Nikolaus Schulz

Rudiger Seidel

The alkaline saponification of acrylonitrile bead polymers provides weakly acidic cation exchangers with little intrinsic color and with reduced residual nitrogen content if the saponification is begun at a temperature Tof from 70 to 120&#xb0; C. and, once a degree of saponification of at least 65% has been reached, is completed at a temperature Tof from 120 to 180&#xb0; C.

Process for the alkaline saponification of crosslinked acrylonitrile bead polymers

Indoles of the formula ##STR1## can be prepared by reaction of a phenylhydrazine of the formula ##STR2## which is unsubstituted in at least one ortho-position, with a ketone of the formula ##STR3## in an aqueous medium in the presence of an acid compound, less than 5 equivalents, based on 1 mol of phenylhydrazine, of an acid compound having a pK value of 1.3-4.5 being employed.

Process for the preparation of indoles

Growing community of inventors

Bergisch Gladbach, Germany

Dieter Irmscher