Phenyltetraline-diphosphonic acids and process for making them
AssigneeHoechst Aktiengesellschaft
InventorWerner Pieper
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Abstract
Novel-1-phenyltetraline-1,4-diphosphonic acids of the formula ##STR1## are made by reacting 1-phenylvinyl-1-phosphonic acids at temperatures of from 120.degree.-210.degree. C.
Claims5
1-phenyl-tetraline-1,4-diphosphonic acids of the formula ##STR2##
A process for making .alpha.- and .beta.-1-phenyl-tetraline-1,4-diphosphonic acids which comprises heating 1-phenylvinyl-1-phosphonic acid to 120.degree.-210.degree. C. until the said diphosphonic acids are formed as reaction products;
- suspending those reaction products in water, in which .beta.-1-phenyltetraline-1,4-diphosphonic acid becomes dissolved and .alpha.-1-phenyltetraline-1,4-diphosphonic acid remains behind as crystalline solid matter;
- and separating said crystaline solid matter from the solution thus obtained.
A process for making .alpha.- and .beta.-1-phenyltetraline-1,4-diphosphonic acids which comprises heating 1-phenylvinyl-1-phosphonic acid to 120.degree.-210.degree. C. until the said disphosphonic acids are formed as reaction products;
- suspending these reaction products in methanol, in which .alpha.-1-phenyltetraline-1,4-diphosphonic acid becomes dissolved and .beta.-1-phenyltetraline-1,4-diphosphonic acid remains behind as crystalline solid matter;
- and separating said crystalline solid matter from the solution thus obtained.
Dependencies are inferred from the claim text.