Rohm Gmbh

Ronm Gmbh

Achim Riemann

Werner Ude

Siegmund Besecke

Guenther Schroeder

Compounds of the formula ##STR1## wherein R is lower alkyl or aryl, Y is oxygen or sulfur, m is 0 or 1, Ar is arylene, and X is halogen, methyl, or aryloxy, or polymers containing repeating units of this kind are prepared from a compound R--P(Y).sub.r Cl.sub.2, where r is 0 or 1 but is never greater than m, by reaction with one or two molar parts of a compound H--ArX in the presence of a Friedel-Crafts catalyst.

Method for making aromatic phosphorus compounds

A method for making 9,9-bis-(4-hydroxyphenyl)-fluorene by reacting fluorenone with phenol at a temperature from 20.degree. to 100.degree. C. in the presence of sulfuric acid of a concentration higher than 70 percent and of a mercaptan, and particularly beta-mercaptopropionic acid, as acidic condensing agents.

Method for making 9,9-bis-(4-hydroxyphenyl)-fluorene

A method for making 4,4'-dihydroxydiphenyl ether from diphenyl ether by oxidatively iodinating diphenyl ether to 4,4'-diiododiphenyl ether and/or 4-hydroxy-4'-iododiphenyl ether, hydrolyzing this product with a base, recovering iodine from the solution containing iodide, and recycling the iodine to the iodination step.

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Marburg, Germany

Achim Riemann