Bayer Aktiengesellschaft

R&uuml;diger Schubart

Hans-Wilhelm Engels

Zinc dithiocarbamates are obtained in especially readily filterable form and high purity when zinc salts are first added, in aqueous solution, to the secondary amines underlying the zinc carbamates, so that a zinc salt complex of the amines is formed, and carbon disulfide and then sodium hydroxide solution are then introduced, with stirring, into the aqueous suspension so obtained, the temperatures being maintained in the range from room temperature to the boiling temperature of carbon disulfide until the reaction has completely finished.

Process for the preparation of zinc dithiocarbamates

This invention relates to a process for the selective preparation of cis-2,6-dimethylpiperazine by reacting (i) a diisopropanolamine mixture comprising compounds having the formulas HN(CH CH(OH)CH ) , HN(CH(CH )CH OH) , and HN(CH(CH )CH OH)(CH CH(OH)CH ) or (ii) 1,2-diaminopropane with ammonia and hydrogen in the presence of a hydrogenation catalyst.

Process for preparing Cis-2,6-dimethylpiperazine

This invention relates to a process for the selective preparation of cis-2,6-dimethylpiperazine by reacting (i) a diisopropanolamine mixture comprising compounds having the formulas HN(CH,CH(OH)CH,),, HN(CH(CH,)CH,OH),, and HN(CH(CH,)CH,OH)(CH,CH(OH)CH,) or (ii) 1,2-diaminopropane with ammonia and hydrogen in the presence of a hydrogenation catalyst.

Growing community of inventors

Gladbach, Germany

Rüdiger Schubart

Growing community of inventors

Gladbach, Germany

R&uuml;diger Schubart

Rüdiger Schubart