Abstract: Benzophenone derivatives having at least one hydroxyl group in the ortho-position relative to the carbonyl group are used for stabilizing numerous substrates against the action of UV light. 1,3-bis-(4-Benzoyl-3-hydroxyphenoxy)-2-propanol is a photo-absorber containing two benzophenone groups. Particularly suitable stabilizers are esters of this substituted propanol with unsaturated carboxylic acids, for example esters of acrylic acid and methacrylic acid. These compounds are prepared by esterifying the substituted propanol with an unsaturated acid or by esterifying the substituted propanol with a saturated acid containing a reactive methylene group and subjecting the product to subsequent condensation with a keto compound. They can be polymerized and are suitable for the preparation of homopolymers and copolymers.

Abstract: Substituted bromofluorobenzene, wherein the fluorine is in para-position and the bromine in meta-position to another substituent, is prepared by direct bromination of the corresponding fluorobenzene derivative. Bromination is advantageously carried out in the presence of a catalyst, preferably a metal or metal salt. The elementary bromine is used in an amount of 0.9 to 1.3 mols per mol of fluorobenzene derivative and the reaction temperature is between 20.degree. and 200.degree. C. The bromofluorobenzene derivatives are suitable for the synthesis of medicaments and plant protective agents.

Abstract: Aromatic 1,3-diketones are produced by reacting aromatic compounds with acetoacetyl fluoride optionally substituted in the .gamma.-position by fluorine, chlorine and/or bromine, in hydrofluoric acid of at least 90% strength at a temperature of from about -40.degree. to +50.degree. C. The products obtained are important starting products and intermediates for the manufacture of dyestuffs, plastics and pharmaceuticals. Furthermore they can be used for the formation of metal complexes and as metal extracting agents, solution intermediaries and solvents.

Abstract: Aromatic 1,3-diketones are produced by reacting aromatic compounds with acetoacetyl fluoride optionally substituted in .gamma.-position by fluorine, chlorine and/or bromine, in hydrofluoric acid of at least 90% strength at a temperature of from about -40 to +50.degree.C. The products obtained are important starting products and intermediates for the manufacture of dyestuffs, plastics and pharmaceuticals. Furthermore they can be used for the formation of metal complexes and metal extracting agents, solution intermediaries and solvents.