摘要:
Hydroxydiphenyls can be prepared by reacting diphenylsulphonic acids or their alkali metal salts with an alkali metal hydroxide at elevated temperature and elevated pressure, in the presence of water. For this purpose, the diphenylsulphonic acids or their alkali metal salts are reacted, at a temperature between 280.degree. and 330.degree. C. and a pressure of up to 120 bar, with an amount of aqueous alkali metal hydroxide having a concentration of at least 50% by weight, such that, after all acidic groups have been neutralized, 3 to 25 mols of alkali metal hydroxide per equivalent of sulphonate group are present in the reaction mixture. Mineral acids are added to the alkaline reaction mixture, after it has been cooled and diluted with water, until the pH value is less than 8, and the precipitated hydroxydiphenyl is isolated at a temperature from -5.degree. C. to +100.degree. C.
摘要:
A new process for the preparation of mono-N-.beta.-cyanoethylanilines, characterized in that a substituted or unsubstituted aniline compound is reacted with acrylonitrile in the presence of active bleaching earth as catalyst at a temperature of between 80.degree. and 200.degree. C. in a nonaqueous reaction medium.
摘要:
A novel mixture containing a number of particular mercaptans, a process for preparing it and its use as advantageous molecular weight regulator in the production of synthetic rubbers are provided.
摘要:
A new process for the preparation of aromatic sulphonic acids, in which the sulphonation of the aromatic compounds is carried out with sulphur trioxide in organic solvents in the presence of hydrogen halide.